Modular shield machine

Abstract

The application relates to the field of shield machines, in particular to a combined assembly type shield machine which comprises a cutter head, a front shield and a shield shell, and further comprises a plurality of driving members, the front shield is coaxially connected to the rear of the cutter head, the shield shell comprises a plurality of supporting shells which are distributed in the circumferential direction of the front shield, the number of the driving members is equal to the number of the supporting shells, the driving member is arranged between the supporting shell and the front shield, and the driving member is used for driving the supporting shell to slide in the radial direction of the front shield; the two ends of the supporting shell in the circumferential direction of the front shield are used for abutting against adjacent supporting shells. In the application, when the driving member drives the supporting shell to move away from the front shield, the two ends of the supporting shell in the circumferential direction of the front shield gradually move away from the adjacent supporting shells, so that the supporting range of the supporting shell is expanded, and the adaptability of the shield machine is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of shield machines, in particular to a combined assembly type shield machine. BACKGROUND

[0002] The shield machine is a tunnel boring machine using the shield method, which integrates light, machine, electricity, liquid, sensing and information technology, and has multiple functions such as excavating soil, cutting rock and conveying slag, and plays a crucial role in tunnel excavation.

[0003] The shield machine mainly includes a cutter head and a shield body, the shield body is located behind the cutter head, and the shield body includes a front shield, a middle shield and a tail shield in a columnar shape, the cutter head is used for cutting soil and rock, the front shield is used for maintaining the stability of the cutter head excavation surface, the middle shield is provided with an oil cylinder for driving the cutter head to rotate, and the tail shield mainly ensures the safe assembly of the supporting pipe piece and pre-provides a grouting pipe to prevent water in the tunnel from flowing into the inside of the shield body.

[0004] After the cutter head cuts, the front shield supports the tunnel formed by the cutter head, and a shield shell is often arranged on the outer periphery of the front shield, which abuts against the inner wall of the tunnel to ensure the stability of the inner wall of the tunnel after excavation, and prevents the inner wall of the tunnel from falling due to vibration caused by the cutter head during work, so as to facilitate the laying of the subsequent supporting pipe piece.

[0005] However, the outer diameter of the shield shell is single, the reuse rate is low, and the economic benefit is poor; when the diameter of the tunnel changes, the original outer diameter of the shield shell cannot meet the new construction requirements, and a new shield shell needs to be installed or left idle to be suitable for the matched shield machine, and the adaptability is poor, which needs to be improved. SUMMARY

[0006] In order to improve the adaptability of the shield machine, the present application provides a combined assembly type shield machine.

[0007] The combined assembly type shield machine provided by the present application adopts the following technical scheme:

[0008] A combined assembly type shield machine, comprising a cutter head, a front shield and a shield shell, further comprising a plurality of driving members, the front shield is coaxially connected behind the cutter head, the shield shell comprises a plurality of supporting shells distributed circumferentially along the front shield, the number of the driving members is equal to the number of the supporting shells, the driving member is arranged between the supporting shell and the front shield, and the driving member is used to drive the supporting shell to slide radially along the front shield; the two ends of the supporting shell along the circumference of the front shield are used to abut against the adjacent supporting shell.

[0009] By adopting the technical scheme, when the driving member drives the supporting shells to move away from the front shield, the two ends of the supporting shells along the circumference of the front shield gradually move away from the adjacent supporting shells to expand the supporting range of the supporting shells, thereby improving the adaptability of the shield tunneling machine. Meanwhile, when the inner wall of the tunnel abuts against the supporting shells, the driving member drives the supporting shells to move away from the front shield, so that the supporting shells abut against the inner wall of the tunnel, thereby weakening the vibration of the supporting shells caused by the cutter head.

[0010] Preferably, the surface of the supporting shell close to the cutter head is provided with a guide surface, the distance of the guide surface to the axis of the front shield gradually increases away from the cutter head, and the guide surface is used for slidingly abutting against the inner wall of the tunnel.

[0011] By adopting the technical scheme, when the cutter head is tunneling, the shield body and the supporting shells move forward with the cutter head, and the guide surface abuts against the inner wall of the tunnel, thereby reducing the probability that the end surface of the supporting shell along the axis of the front shield scratches the inner wall of the tunnel to cause the falling of the earth and rock; meanwhile, the guide surface abuts against the inner wall of the tunnel, so that the earth of the inner wall of the tunnel can be compacted under the action of the guide surface, thereby improving the stability of the inner wall of the tunnel to facilitate the laying of the subsequent supporting segments.

[0012] Preferably, a plurality of blocking bars are further included, the number of the blocking bars is equal to the number of the supporting shells, a spring is arranged between the blocking bar and the front shield, the spring is provided with a pre-tightening force for moving the blocking bar away from the front shield; the two sides of the supporting shell along the circumference of the front shield are each provided with a driving surface, the driving surface abuts against the blocking bar, and the distance between the two driving surfaces in the same supporting shell gradually increases away from the axis of the front shield.

[0013] By adopting the technical scheme, when the supporting shells move away from the front shield under the action of the driving member, the blocking bar abuts against the driving surface, the driving surface limits the blocking bar, and the blocking bar moves away from the front shield under the action of the pre-tightening force of the spring, thereby making the blocking bar compensate for the gap generated by the mutual moving away of the supporting shells, reducing the probability that the small debris such as the groundwater, the earth and the gravel in the tunnel enters between the front shield and the supporting shells, facilitating the normal operation of the front shield, reducing the probability that the inner wall of the tunnel collapses due to the serious water and soil loss, and improving the construction safety. When the driving member drives the supporting shells to move close to the front shield, the driving surface slidingly abuts against the blocking bar, so that the blocking bar compresses the spring under the action of the driving surface and gradually resets.

[0014] Preferably, the front shield is fixedly connected with a limiting column, the axis of the limiting column intersects with the axis of the front shield, the blocking bar is provided with a blind hole for slidingly embedding the limiting column, and the spring is sleeved on the outer periphery of the blocking bar.

[0015] By adopting the technical scheme, the axis of the spring intersects with the axis of the front shield as much as possible, so that the elastic force of the spring is used as much as possible to make the blocking bar away from the front shield, the probability of spring bending failure is reduced, that is, the elastic force of the spring is used as much as possible to make the blocking bar away from the surface of the front shield to abut against the inner wall of the tunnel, so as to avoid the mud and water in the tunnel entering between the front shield and the supporting shell as much as possible, and the stability of the blocking bar abutting against the driving surface is improved.

[0016] Preferably, the supporting shell is hinged with a support plate, one end of the support plate away from the supporting shell is hinged with a sliding seat, the front shield is provided with a sliding rail for sliding connection of the sliding seat, the sliding rail extends along the circumference of the front shield; the driving member is an oil cylinder, the oil cylinder is fixedly connected to the front shield, and the piston rod of the oil cylinder is fixedly connected to the supporting shell.

[0017] By adopting the technical scheme, with the sliding of the supporting shell, the support plate rotates, so that the sliding seat slides along the sliding rail, and the supporting shell is supported by the support plate and the oil cylinder, and the stability of the supporting shell is improved.

[0018] Preferably, the driving surface is provided with a mounting groove, a limiting plate is slidably embedded in the mounting groove, and the limiting plate is fixedly connected with a rack, the support plate is hinged to the supporting shell through a hinge shaft, the hinge shaft is coaxially fixedly connected with a gear, and the gear is engaged with the rack; the blocking bar is provided with a limiting groove communicating with the mounting groove, when the supporting shell is away from the front shield, the limiting plate extends out of the mounting groove and extends into the limiting groove, the groove wall of the limiting groove is provided with a limiting surface for sliding abutment of the limiting plate, and the limiting surface gradually approaches the front shield with the distance away from the mounting groove.

[0019] By adopting the technical scheme, when the supporting shell is away from the front shield, the rotation of the support plate drives the gear to slide the rack, so that the limiting plate slides out of the mounting groove and extends into the limiting groove, and the limiting surface slides against the limiting plate, so as to avoid the extrusion force of the rock, soil, underground water and other residues in the tunnel wall on the blocking bar to make the blocking bar and the driving surface separate, thereby improving the stability of the blocking bar; and the limiting surface slides against the limiting plate, so that the limiting surface can abut against the limiting plate during the movement of the blocking bar, thereby improving the stability of the blocking bar when the supporting shell is at different distances from the front shield.

[0020] Preferably, the support plate comprises a connecting rod and two support rods, the two support rods are arranged side by side, and the connecting rod is fixedly connected between the two support rods; the sliding rail is provided with two, the two sliding rails are distributed along the axis of the front shield, the length direction of the connecting rod is the same as the axis of the front shield, one end of the support rod is hinged to the supporting shell, the other end of the support rod is hinged with the sliding seat, and the two sliding seats are respectively slidably connected to the two sliding rails.

[0021] By adopting the technical scheme, the support shell is supported by two support rods, so that the stability of the support shell when supporting the inner wall of the tunnel is improved, and the probability of vibration of the support shell due to the cutting of the rock wall by the cutter head is reduced.

[0022] Preferably, an included angle formed by the two surfaces of the blocking strip along the circumference of the front shield is denoted as angle A, and an included angle between adjacent driving surfaces in the support shell is denoted as angle B, the sizes of the angle A and the angle B are equal, and the angle A and the angle B are both directed towards the axis of the front shield.

[0023] By adopting the technical scheme, as the support shell moves away, the two surfaces of the blocking strip along the circumference of the front shield can always abut against the driving surface based on the elastic force, and by the equal sizes and the same directions of the angle A and the angle B, the contact area between the blocking strip and the driving surface is increased, so that the probability of inclination of the blocking strip in the sliding process is reduced, and the stability of the blocking strip is improved, so that the protection effect of the blocking strip on the soil, underground water and gravel in the tunnel is improved.

[0024] In summary, the present application has at least one of the following beneficial technical effects:

[0025] 1. When the driving member drives the support shell to move away from the front shield, the two ends of the support shell along the circumference of the front shield gradually move away from the adjacent support shell, so as to expand the support range of the support shell, thereby improving the adaptability of the shield tunneling machine;

[0026] 2. By arranging the blocking strip and the spring, the pre-tightening force of the spring makes the blocking strip abut against the surfaces of the adjacent support shells that move close to each other, so as to avoid the soil, moisture and other small debris in the inner wall of the tunnel from entering between the support shell and the front shield, thereby reducing the influence of the debris on the operation of the driving member and the front shield and other components;

[0027] 3. By slidingly abutting the limiting plate against the limiting surface, even if the support shell has different distances from the front shield, the stability of the blocking strip can still be improved based on the abutment of the limiting surface and the limiting plate. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a schematic diagram of the overall structure of the embodiment of the present application.

[0029] Figure 2 is a schematic diagram of the local structure of the embodiment of the present application.

[0030] Figure 3 is a broken view of the embodiment of the present application.

[0031] Explanation of reference signs: 1, cutter head; 2, front shield; 21, sliding rail; 22, limiting column; 3, shield shell; 31, supporting shell; 311, driving surface; 312, mounting groove; 313, communication groove; 314, limiting plate; 315, rack; 316, guide surface; 4, driving member; 41, oil cylinder; 5, support plate; 51, support rod; 511, sliding seat; 512, hinged shaft; 513, gear; 52, connecting rod; 6, blocking bar; 61, spring; 62, limiting groove; 63, limiting surface. DETAILED DESCRIPTION

[0032] The following description will be made in conjunction with the accompanying drawings. Figures 1-3 The application is further described in detail.

[0033] Reference will be made to Figure 1 and Figure 2 The embodiment of the application discloses a combined assembly type shield machine, comprising a cutter head 1, a front shield 2, a shield shell 3 and a plurality of driving members 4, the cutter head 1 is used for cutting soil and rock, the front shield 2 is coaxially connected to the rear of the cutter head 1; the shield shell 3 comprises a plurality of supporting shells 31 distributed equidistantly along the circumference of the front shield 2, the supporting shell 31 is located outside the front shield 2, the projection of the supporting shell 31 along the axis of the front shield 2 is in the shape of a circular arc, the two ends of the supporting shell 31 along the circumference of the front shield 2 are used for abutting against adjacent supporting shells 31, and when the two ends of the supporting shell 31 along the circumference of the front shield 2 abut against adjacent supporting shells 31, the shield shell 3 is coaxial to the front shield 2, and the projection of the shield shell 3 along the axis of itself is in the shape of a circle.

[0034] The number of the driving members 4 is equal to the number of the supporting shells 31, the driving member 4 is an oil cylinder 41, in the embodiment, the number of the oil cylinders 41 is six, and in other embodiments, the number of the oil cylinders 41 can be eight, ten or the like. All the oil cylinders 41 are distributed equidistantly along the circumference of the front shield 2, the oil cylinder 41 is fixedly connected to the front shield 2, and the piston rod of all the oil cylinders 41 is fixedly connected to all the supporting shells 31 one by one, the piston rod extends and retracts along the radial direction of the front shield 2, so that the oil cylinder 41 drives the supporting shell 31 to slide along the radial direction of the front shield 2, thereby changing the supporting range of the supporting shell 31 to the inner wall of the tunnel, and improving the adaptability of the shield machine.

[0035] Reference will be made to Figure 2 and Figure 3Each support shell 31 is hingedly connected with two support plates 5 located on both sides of the oil cylinder 41, and the two support plates 5 are symmetrical about the oil cylinder 41. Specifically, the support plate 5 includes two support rods 51 arranged side by side and a connecting rod 52 fixedly connected between the two support rods 51, the length direction of the connecting rod 52 is the same as the axial direction of the front shield 2, so that the projection of the support plate 5 along the thickness direction thereof is H-shaped, the distribution direction of the two support rods 51 is the same as the axial direction of the front shield 2, and the axial direction of the support rod 51 is perpendicular to the axial direction of the support shell 31. One end of the support rod 51 is hingedly connected to the front shield 2, and the other end of the support rod 51 is hingedly connected with a sliding seat 511. The outer periphery of the front shield 2 is coaxially and fixedly connected with two slide rails 21, the two slide rails 21 are distributed in the circumferential direction of the front shield 2, and the sliding seat 511 is slidingly connected to the slide rails 21. The hinge shaft 512 between the support rod 51 and the sliding seat 511 and the hinge shaft 512 between the support rod 51 and the support shell 31 are both parallel to the axis of the front shield 2. When the piston rod of the oil cylinder 41 is not extended, the two ends of the support shell 31 in the circumferential direction of the front shield 2 abut against the adjacent support shell 31, and when the piston rod of the oil cylinder 41 is extended, the two ends of the support shell 31 in the circumferential direction of the front shield 2 gradually move away from each other, the sliding seats 511 hingedly connected with the two support plates 5 gradually move away from each other, and the support shells 31 are limited and supported.

[0036] The combined assembly type shield tunneling machine further includes a plurality of blocking bars 6, the number of the blocking bars 6 being equal to the number of the support shells 31. A plurality of springs 61 distributed in the axial direction of the front shield 2 are arranged between each blocking bar 6 and the front shield 2, one end of the spring 61 is fixedly connected to the outer surface of the front shield 2, the other end of the spring 61 is fixedly connected to the blocking bar 6, and the spring 61 is provided with a pre-tightening force for moving the blocking bar 6 away from the front shield 2. In the embodiment, the number of the springs 61 is two, so as to improve the stability of the sliding of the blocking bar 6, and in other embodiments, the number of the springs 61 can be three, four, etc. A plurality of limiting columns 22 are fixedly connected to the outer periphery of the front shield 2, the number of the limiting columns 22 is equal to the number of the springs 61, the axis of the limiting column 22 intersects the axis of the front shield 2, the blocking bar 6 is provided with a blind hole for sliding embedding of the limiting column 22, and the spring 61 is sleeved on the outer periphery of the limiting column 22, so as to limit the extension direction of the spring 61 by the limiting column 22.

[0037] The supporting shell 31 is provided with a driving surface 311 on both sides of the front shield 2 in the circumferential direction, the driving surface 311 is attached to the blocking strip 6, and the driving surface 311 is used for the blocking strip 6 to slide and abut. In the same supporting shell 31, the distance between the two driving surfaces 311 gradually increases away from the front shield 2. The two surfaces of the blocking strip 6 in the circumferential direction of the front shield 2 are respectively parallel to the two driving surfaces 311 of the adjacent supporting shell 31 that are close to each other. The two surfaces of the blocking strip 6 in the circumferential direction of the front shield 2 are respectively used for sliding and attaching the driving surface 311 provided by the adjacent supporting shell 31, so as to avoid the underground water, soil and small debris in the tunnel from entering between the front shield 2 and the supporting shell 31. The included angle formed by the two surfaces of the blocking strip 6 in the circumferential direction of the front shield 2 is denoted as angle A. In different supporting shells 31, the included angle between the adjacent driving surfaces 311 is denoted as angle B. The sizes of angle A and angle B are equal, and both angle A and angle B are towards the axis of the front shield 2. In the process of moving away from the front shield 2, the elastic force of the spring 61 enables the two surfaces of the blocking strip 6 in the circumferential direction of the front shield 2 to slide and abut on the driving surface 311. The blocking strip 6 is limited by the driving surface 311, so as to avoid the probability of the blocking strip 6 tilting in the sliding process. In the process of moving close to the front shield 2, the blocking strip 6 slides and abuts on the driving surface 311 through the driving surface 311, so as to gradually compress the spring 61.

[0038] Referring to Figure 2 and Figure 3The two driving surfaces 311 in the same support shell 31 are provided with mounting grooves 312, the mounting grooves 312 are slidably embedded with limiting plates 314, the sliding direction of the limiting plates 314 is perpendicular to the axial direction of the front shield 2, each limiting plate 314 is fixedly connected with two racks 315, the length direction of the rack 315 is the same as the sliding direction of the limiting plate 314, and the length direction of the rack 315 is perpendicular to the hinge shaft 512 between the support rod 51 and the support shell 31; the support rod 51 is hinged to the support shell 31 through the hinge shaft 512, the hinge shaft 512 is fixedly connected to the support rod 51, the hinge shaft 512 is coaxially fixedly connected with two gears 513, the support shell 31 is provided with a plurality of communication grooves 313 which are communicated with the mounting grooves 312, the number of the communication grooves 313 is equal to the number of the gears 513, the gears 513 are rotatably embedded in the communication grooves 313 one by one, and the gears 513 are engaged with the racks 315 one by one; when the piston rod of the oil cylinder 41 extends, the connecting plate drives the gear 513 to rotate, and the gear 513 drives the limiting plate 314 to gradually extend out of the mounting groove 312 through the meshing transmission between the gear 513 and the rack 315. The two surfaces of the blocking strip 6 along the circumferential direction of the front shield 2 are provided with limiting grooves 62, the two limiting grooves 62 are respectively communicated with the mounting grooves 312 provided on the adjacent support shells 31, and when the support shell 31 moves away from the front shield 2 due to the extension of the piston rod of the oil cylinder 41, the limiting plate 314 extends out of the mounting groove 312 and extends into the limiting groove 62; the groove wall of the limiting groove 62 is provided with a limiting surface 63, the limiting surface 63 is used for slidingly abutting against the limiting plate 314, and the limiting surface 63 gradually approaches the front shield 2 away from the mounting groove 312. When the limiting surface 63 abuts against the limiting plate 314, the limiting surface 63 gradually approaches the front shield 2 away from the mounting groove 312, so as to limit the position of the blocking strip 6 through the limiting plate 314, and to avoid that the blocking strip 6 causes a large gap between the driving surface 311 and the blocking strip 6 under the extrusion of the gravel and soil, so as to reduce the probability that the gravel and soil enter between the front shield 2 and the support shell 31 to affect the normal work of the oil cylinder 41 and other parts; and the limiting surface 63 slides against the limiting plate 314, so that the blocking strip 6 can be at different positions, and the stability of the blocking strip 6 at different positions is improved.

[0039] With reference to Figure 1 The end face of the support shell 31 close to the cutter head 1 is provided with a guide surface 316, when the two ends of the support shell 31 along the circumferential direction of the front shield 2 abut against the adjacent support shells 31, the projection of the guide surface 316 along the axial direction of the front shield 2 is circular, the distance from the guide surface 316 to the axis of the front shield 2 gradually increases away from the cutter head 1, and the guide surface 316 is used for slidingly abutting against the inner wall of the tunnel, so as to compact the soil of the inner wall of the tunnel formed by cutting the cutter head 1, and facilitate the installation of the subsequent support pipe pieces.

[0040] The implementation principle of the combined assembly type shield machine is as follows: when the telescopic rod of the oil cylinder 41 is not extended, the supporting shells 31 abut against each other along the circumferential two ends of the front shield 2, and the outer surfaces of the supporting shells 31 are used to abut against the inner wall of the tunnel to support the inner wall of the tunnel; when the telescopic rod of the oil cylinder 41 is extended, the supporting shells 31 gradually move away from the front shield 2 to expand the supporting range of the supporting shells 31, at this time, the supporting shells 31 support and protect the large rocks, and the supporting shells 31 move away from the front shield 2, so that the blocking bars 6 slide and fit the driving surface 311 to make up the small gap caused by the expansion of the supporting range of the supporting shells 31, and when the supporting shells 31 move away from the front shield 2, the connecting plates rotate to make the gear 513 rotate, so that the rack 315 drives the limiting plate 314 to move, the limiting plate 314 slides and abuts against the limiting surface 63, thereby improving the stability of the blocking bars 6, so as to reduce the fine slag such as mud, underground water and gravel into the front shield 2 and the supporting shells 31, and to avoid the influence of the slag on the operation of the oil cylinder 41 and other parts as much as possible.

[0041] The above are preferred embodiments of the present application, and do not limit the protection scope of the present application, therefore: any equivalent changes made on the structure, shape, principle of the present application should be covered within the protection scope of the present application.

Claims

1. A modular tunnel boring machine, comprising a cutterhead (1), a front shield (2), and a shield shell (3), characterized in that: It also includes multiple driving components (4), the front shield (2) is coaxially connected to the rear of the cutter head (1), the shield shell (3) includes multiple support shells (31) distributed circumferentially along the front shield (2), the number of driving components (4) is equal to the number of support shells (31), the driving components (4) are disposed between the support shells (31) and the front shield (2), and the driving components (4) are used to drive the support shells (31) to slide radially along the front shield (2); the two ends of the support shells (31) along the circumferential direction of the front shield (2) are used to abut against adjacent support shells (31). It also includes multiple blocking strips (6), the number of which is equal to the number of the support shells (31), and a spring (61) is provided between the blocking strips (6) and the front shield (2). The spring (61) has a preload force that causes the blocking strips (6) to move away from the front shield (2). The support shell (31) has driving surfaces (311) on both sides of the front shield (2) circumferentially. The driving surfaces (311) abut against the blocking strips (6). In the same support shell (31), the distance between the two driving surfaces (311) gradually increases as it moves away from the axis of the front shield (2). When the support shell (31) moves away from the front shield (2) under the action of the drive member (4), the blocking strip (6) abuts against the drive surface (311), the drive surface (311) limits the blocking strip (6), and under the action of the spring (61) preload, the blocking strip (6) moves away from the front shield (2) so that the blocking strip (6) can fill the gap caused by the support shells (31) moving away from each other; when the drive member (4) drives the support shell (31) to approach the front shield (2), the blocking strip (6) slides against the drive surface (311) so that the blocking strip (6) compresses the spring (61) and gradually resets under the action of the drive surface (311).

2. The modular tunnel boring machine according to claim 1, characterized in that: The support shell (31) has a guide surface (316) on the surface near the cutterhead (1). The distance from the guide surface (316) to the axis of the front shield (2) gradually increases as it moves away from the cutterhead (1). The guide surface (316) is used to slide against the inner wall of the tunnel.

3. The modular tunnel boring machine according to claim 1, characterized in that: The front shield (2) is fixedly connected to a limiting post (22), the axis of the limiting post (22) intersects with the axis of the front shield (2), the blocking strip (6) is provided with a blind hole for the limiting post (22) to slide into, and the spring (61) is sleeved on the outer periphery of the blocking strip (6).

4. The modular tunnel boring machine according to claim 1, characterized in that: The support shell (31) is hinged to a support plate (5), and a slide block (511) is hinged to one end of the support plate (5) away from the support shell (31). The front shield (2) is provided with a slide rail (21) for sliding connection of the slide block (511), and the slide rail (21) extends circumferentially along the front shield (2). The driving component (4) is a hydraulic cylinder (41), which is fixedly connected to the front shield (2), and the piston rod of the hydraulic cylinder (41) is fixedly connected to the support shell (31).

5. The modular tunnel boring machine according to claim 4, characterized in that: The driving surface (311) is provided with a mounting groove (312), a limiting plate (314) is slidably embedded in the mounting groove (312), and a rack (315) is fixedly connected to the limiting plate (314). The support plate (5) is hinged to the support shell (31) by a hinge shaft (512), and a gear (513) is fixedly connected to the hinge shaft (512) on the same axis. The gear (513) meshes with the rack (315). The blocking strip (6) is provided with a limiting groove (62) that communicates with the mounting groove (312). When the support shell (31) moves away from the front shield (2), the limiting plate (314) extends out of the mounting groove (312) and into the limiting groove (62). The groove wall of the limiting groove (62) is provided with a limiting surface (63) for sliding against the limiting plate (314). The limiting surface (63) gradually moves closer to the front shield (2) as it moves away from the mounting groove (312).

6. The modular tunnel boring machine according to claim 4, characterized in that: The support plate (5) includes a connecting rod (52) and two support rods (51). The two support rods (51) are arranged side by side, and the connecting rod (52) is fixedly connected between the two support rods (51). There are two slide rails (21), which are distributed along the axial direction of the front shield (2). The length direction of the connecting rod (52) is the same as the axial direction of the front shield (2). One end of the support rod (51) is hinged to the support shell (31), and the other end of the support rod (51) is hinged to the slide block (511). The two slide blocks (511) are slidably connected to the two slide rails (21).

7. The modular tunnel boring machine according to claim 1, characterized in that: The included angle formed by the two surfaces of the blocking strip (6) along the circumference of the front shield (2) is denoted as angle A. In different support shells (31), the included angle between adjacent driving surfaces (311) is denoted as angle B. The size of angle A and angle B are equal, and angle A and angle B are both oriented toward the axis of the front shield (2).

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