A tunnel boring machine main unit and a tunnel boring machine

Abstract

This invention provides a tunnel boring machine (TBM) main unit and a TBM, belonging to the technical field of tunnel boring equipment. The TBM main unit includes a cutterhead for excavating a circular cross-section tunnel, a front shield for supporting the circular cross-section tunnel, a widening device for widening the circular cross-section tunnel to form an irregular cross-section tunnel, and a rear shield for supporting the irregular cross-section tunnel. The front shield is equipped with a front telescopic shield that can extend backward and retract forward, and the rear shield is equipped with a rear telescopic shield that can extend forward and retract backward. Both the front and rear telescopic shields include at least two circumferentially spaced sub-shields, each sub-shield equipped with an independent telescopic drive mechanism. The sub-shields of the front and rear telescopic shields correspond front to back. During construction, only the portion of the tunnel widened by the widening device is exposed; the un-widened and already widened tunnel walls are in a supported state, greatly reducing safety risks.

Description

Technical Field

[0001] This invention relates to a tunnel boring machine (TBM) host and a TBM, belonging to the technical field of tunnel boring equipment. Background Technology

[0002] In tunnel construction, irregular cross-section tunnels are a common type of tunnel, mainly including horseshoe-shaped, archway-shaped, and rectangular tunnels. Traditional irregular cross-section tunnel boring machines use meshing multi-cutterheads, which have a very complex structure. Furthermore, when encountering hard rock during excavation, the matching cutters cannot withstand rock hardness exceeding 80 MPa, and there are blind spots in the cutting process.

[0003] Patent application CN118187882A discloses a shield tunneling excavation device. This device includes a cutterhead and a main beam. Variable amplitude cutting devices (i.e., widening devices) are installed on both sides of the main beam. The cutterhead and the variable amplitude cutting devices work together to excavate a circular outline first. Then, the variable amplitude cutting devices widen the sickle-shaped area to the left and right wings, forming a horseshoe-shaped tunnel. A movable shield (i.e., a rear shield) is installed in the middle section of the main beam to enclose the variable amplitude cutting devices. The movable shield includes a top shield and side shields. After the variable amplitude cutting devices widen the sickle-shaped area a certain distance, the movable shield can promptly follow and temporarily support the tunnel arch outline.

[0004] In fact, the aforementioned excavation device also includes a front shield, which provides temporary support for the circular cross-section tunnel excavated by the cutterhead. According to common knowledge in the field, the front shield moves forward along with the cutterhead during excavation. Before widening the horseshoe-shaped cross-section tunnel, a certain distance is formed between the front and rear shields, exposing a ring of the circular cross-section tunnel for the widening device to excavate. However, the widening device has a limited excavation speed. While excavating one location on the circumference, other locations are exposed without support. If encountering rock strata with poor geological conditions, the construction risk is extremely high, and a tunnel collapse would result in a very serious safety accident. Furthermore, the rear shield in the aforementioned excavation device only moves forward to temporarily support the tunnel after the horseshoe-shaped cross-section tunnel widening is completed. However, the widening device also operates piecemeal, leaving the already widened areas exposed for extended periods, which also poses a significant safety risk. Summary of the Invention

[0005] The purpose of this invention is to provide a tunnel boring machine (TBM) host to solve the problem in the prior art where, when the excavation device is excavating one position in the circumferential direction, other positions are exposed without support, resulting in very high construction risks. It also addresses the issue that in existing TBMs, the rear shield only moves forward to support the tunnel after the horseshoe-shaped cross-section tunnel excavation is completed, while the excavation device operates piecemeal, leaving the already excavated areas exposed for extended periods, leading to significant safety risks. Furthermore, this invention aims to provide a TBM that solves the aforementioned problems.

[0006] To achieve the above objectives, the tunnel boring machine host of the present invention adopts the following technical solution:

[0007] A tunnel boring machine (TBM) main unit includes a cutterhead for excavating a circular cross-section tunnel, a front shield for supporting the circular cross-section tunnel, an enlargement device for enlarging the circular cross-section tunnel to form an irregular cross-section tunnel, and a rear shield for supporting the irregular cross-section tunnel. The front shield is equipped with a front telescopic shield that can extend backward and retract forward, and the rear shield is equipped with a rear telescopic shield that can extend forward and retract backward, or the rear shield itself is a rear telescopic shield that can move back and forth relative to the main beam. Both the front telescopic shield and the rear telescopic shield include at least two circumferentially spaced sub-shields, each sub-shield is equipped with an independent telescopic drive mechanism that can control the forward and backward movement of the sub-shield, and the sub-shields of the front telescopic shield and the rear telescopic shield correspond to each other front and back.

[0008] The beneficial effects of the above technical solution are as follows: This invention is an improved invention, which adds a front telescopic shield to the front shield and a rear telescopic shield to the rear shield, or the rear shield itself is a rear telescopic shield that can move back and forth relative to the main beam. At the same time, both the front and rear telescopic shields include at least two circumferentially spaced sub-shields, and each sub-shield is equipped with an independent telescopic drive mechanism, which can independently control the forward and backward movement of the corresponding sub-shield. The sub-shields of the front telescopic shield correspond to the sub-shields of the rear telescopic shield. In this way, during the process of the cutterhead excavating the circular cross-section tunnel, each sub-shield of the front telescopic shield can extend backward to support the circular cross-section tunnel. When it is necessary to widen the circular cross-section tunnel, one of the sub-shields of the front telescopic shield retracts forward, exposing a small section of the circular cross-section tunnel, while the other parts are supported by the other sub-shields of the front telescopic shield, which greatly reduces the construction risk. After the expansion excavation device excavates a small section of the tunnel with an irregular cross-section, the corresponding shield body of the rear telescopic shield extends forward to support the tunnel with an irregular cross-section in a timely manner. Therefore, during the entire construction process, only the part of the tunnel excavated by the expansion excavation device is exposed, while the tunnel walls of the unexcavated and the already excavated tunnels are in a supported state, which greatly reduces safety risks and the probability of safety accidents.

[0009] Furthermore, the rear shield is fixedly installed relative to the main beam of the tunnel boring machine host, and the rear telescopic shield is installed on the rear shield. The rear shield has a sandwich structure with the same shape as the rear shield, and each sub-shield of the rear telescopic shield is set in the sandwich of the rear shield.

[0010] Furthermore, the rear shield is fixedly installed relative to the main beam of the tunnel boring machine host, and the rear telescopic shield is installed on the rear shield. The rear shield has an arc-shaped sandwich structure, and each sub-shield of the rear telescopic shield is arc-shaped and is set in the sandwich of the rear shield.

[0011] Furthermore, the front shield has a sandwich structure that matches the shape of the front shield, and each sub-shield of the front telescopic shield is set inside the sandwich of the front shield.

[0012] Furthermore, the excavation device includes a mounting base that is guided and installed on the main beam of the tunnel boring machine host in the front-back direction. The mounting base is connected to a telescopic drive device for driving the mounting base to move back and forth. A telescopic excavation arm with a slewing axis extending back and forth is installed on the mounting base through a slewing drive structure. The telescopic excavation arm is perpendicular to the main beam and its end is connected to a rock breaking device.

[0013] Furthermore, the mounting base includes a ring body sleeved on the outside of the main beam. At least part of the outer circumferential surface of the ring body is a cylindrical surface. A front stop is provided at the front end of the ring body and a rear stop is provided at the rear end. The end of the telescopic excavator arm is clamped between the front stop and the rear stop and fits against the cylindrical surface of the ring body through an arc surface. A telescopic driver is connected between the telescopic excavator arm and the mounting base for driving the telescopic excavator arm to rotate along the cylindrical surface of the ring body.

[0014] Furthermore, the excavation direction of the rock-breaking device is from back to front, and in the direction perpendicular to the front-back direction, the length of the rear stop is greater than the length of the front stop.

[0015] Furthermore, the rear stop and / or the front stop are provided with wear-resistant plates that contact the sides of the telescopic excavator arm.

[0016] Furthermore, the end of the telescopic excavator arm is provided with a guide structure that guides and cooperates with the rear stop and / or the front stop in the circumferential direction.

[0017] Furthermore, the telescopic excavating arms are arranged in pairs, with the two telescopic excavating arms in a pair located on the left and right sides of the main beam, respectively. Each telescopic excavating arm is connected to a rock breaking device at its end, and each telescopic excavating arm is connected to a telescopic actuator between itself and the mounting base. One end of the two telescopic actuators corresponding to a pair of telescopic excavating arms is hinged to the mounting base through the same pin.

[0018] Furthermore, the rotary drive structure includes a rotary bearing, which includes a fixed ring fixedly disposed relative to the mounting base and a rotary ring that can rotate relative to the mounting base and whose rotation axis extends back and forth. A gear ring is provided on the fixed ring or the rotary ring. The rotary drive structure also includes a rotary power source and a drive gear installed at the output end of the rotary power source. The drive gear meshes with the gear ring, and the telescopic excavation arm is fixed on the rotary ring.

[0019] Furthermore, the excavation device also includes a bottom excavation mechanism connected to the lower part of the mounting base and used for excavating the bottom of the tunnel. The bottom excavation mechanism includes a connecting arm connected to the mounting base, and telescopic arms that can extend and retract vertically are connected to the left and right ends of the connecting arm, and excavation rollers are connected to the ends of the two telescopic arms respectively.

[0020] Furthermore, the two excavating drums are arranged symmetrically on the left and right, and the cutting tools on both excavating drums are arranged in a spiral shape to transport the excavated slag towards the center.

[0021] Furthermore, the tunnel boring machine also includes a star wheel slag collection mechanism connected to the lower part of the main beam. The star wheel slag collection mechanism is located behind the two cutting drums to collect the slag conveyed between the two cutting drums.

[0022] To achieve the above objectives, the tunnel boring machine of this invention adopts the following technical solution:

[0023] A tunnel boring machine includes a main unit and supporting equipment. The main unit includes a cutterhead for excavating a circular cross-section tunnel, a front shield for supporting the circular cross-section tunnel, an enlargement device for enlarging the circular cross-section tunnel to form an irregular cross-section tunnel, and a rear shield for supporting the irregular cross-section tunnel. The front shield is equipped with a front telescopic shield that can extend backward and retract forward, and the rear shield is equipped with a rear telescopic shield that can extend forward and retract backward, or the rear shield itself is a rear telescopic shield that can move back and forth relative to the main beam. Both the front telescopic shield and the rear telescopic shield include at least two circumferentially spaced sub-shields. Each sub-shield is equipped with an independent telescopic drive mechanism that can control the forward and backward movement of the sub-shield. The sub-shields of the front telescopic shield and the sub-shields of the rear telescopic shield correspond to each other front and back.

[0024] The beneficial effects of the above technical solution are as follows: This invention is an improved invention, which adds a front telescopic shield to the front shield and a rear telescopic shield to the rear shield, or the rear shield itself is a rear telescopic shield that can move back and forth relative to the main beam. At the same time, both the front and rear telescopic shields include at least two circumferentially spaced sub-shields, and each sub-shield is equipped with an independent telescopic drive mechanism, which can independently control the forward and backward movement of the corresponding sub-shield. The sub-shields of the front telescopic shield correspond to the sub-shields of the rear telescopic shield. In this way, during the process of the cutterhead excavating the circular cross-section tunnel, each sub-shield of the front telescopic shield can extend backward to support the circular cross-section tunnel. When it is necessary to widen the circular cross-section tunnel, one of the sub-shields of the front telescopic shield retracts forward, exposing a small section of the circular cross-section tunnel, while the other parts are supported by the other sub-shields of the front telescopic shield, which greatly reduces the construction risk. After the expansion excavation device excavates a small section of the tunnel with an irregular cross-section, the corresponding shield body of the rear telescopic shield extends forward to support the tunnel with an irregular cross-section in a timely manner. Therefore, during the entire construction process, only the part of the tunnel excavated by the expansion excavation device is exposed, while the tunnel walls of the unexcavated and the already excavated tunnels are in a supported state, which greatly reduces safety risks and the probability of safety accidents.

[0025] Furthermore, the rear shield is fixedly mounted relative to the main beam of the host machine, and the rear telescopic shield is installed on the rear shield. The rear shield has a sandwich structure with the same shape as the rear shield, and each sub-shield of the rear telescopic shield is set in the sandwich of the rear shield.

[0026] Furthermore, the rear shield is fixedly mounted relative to the main beam of the host machine, and the rear telescopic shield is installed on the rear shield. The rear shield has an arc-shaped sandwich structure, and each sub-shield of the rear telescopic shield is arc-shaped and is set in the sandwich of the rear shield.

[0027] Furthermore, the front shield has a sandwich structure that matches the shape of the front shield, and each sub-shield of the front telescopic shield is set inside the sandwich of the front shield.

[0028] Furthermore, the excavation device includes a mounting base that is guided and installed on the main beam of the host machine in the front-rear direction. The mounting base is connected to a telescopic drive device for driving the mounting base to move back and forth. A telescopic excavation arm with a slewing axis extending back and forth is installed on the mounting base through a slewing drive structure. The telescopic excavation arm is perpendicular to the main beam and its end is connected to a rock breaking device.

[0029] Furthermore, the mounting base includes a ring body sleeved on the outside of the main beam. At least part of the outer circumferential surface of the ring body is a cylindrical surface. A front stop is provided at the front end of the ring body and a rear stop is provided at the rear end. The end of the telescopic excavator arm is clamped between the front stop and the rear stop and fits against the cylindrical surface of the ring body through an arc surface. A telescopic driver is connected between the telescopic excavator arm and the mounting base for driving the telescopic excavator arm to rotate along the cylindrical surface of the ring body.

[0030] Furthermore, the excavation direction of the rock-breaking device is from back to front, and in the direction perpendicular to the front-back direction, the length of the rear stop is greater than the length of the front stop.

[0031] Furthermore, the rear stop and / or the front stop are provided with wear-resistant plates that contact the sides of the telescopic excavator arm.

[0032] Furthermore, the end of the telescopic excavator arm is provided with a guide structure that guides and cooperates with the rear stop and / or the front stop in the circumferential direction.

[0033] Furthermore, the telescopic excavating arms are arranged in pairs, with the two telescopic excavating arms in a pair located on the left and right sides of the main beam, respectively. Each telescopic excavating arm is connected to a rock breaking device at its end, and each telescopic excavating arm is connected to a telescopic actuator between itself and the mounting base. One end of the two telescopic actuators corresponding to a pair of telescopic excavating arms is hinged to the mounting base through the same pin.

[0034] Furthermore, the rotary drive structure includes a rotary bearing, which includes a fixed ring fixedly disposed relative to the mounting base and a rotary ring that can rotate relative to the mounting base and whose rotation axis extends back and forth. A gear ring is provided on the fixed ring or the rotary ring. The rotary drive structure also includes a rotary power source and a drive gear installed at the output end of the rotary power source. The drive gear meshes with the gear ring, and the telescopic excavation arm is fixed on the rotary ring.

[0035] Furthermore, the excavation device also includes a bottom excavation mechanism connected to the lower part of the mounting base and used for excavating the bottom of the tunnel. The bottom excavation mechanism includes a connecting arm connected to the mounting base, and telescopic arms that can extend and retract vertically are connected to the left and right ends of the connecting arm, and excavation rollers are connected to the ends of the two telescopic arms respectively.

[0036] Furthermore, the two excavating drums are arranged symmetrically on the left and right, and the cutting tools on both excavating drums are arranged in a spiral shape to transport the excavated slag towards the center.

[0037] Furthermore, the main unit also includes a star wheel slag collection mechanism connected to the lower part of the main beam. The star wheel slag collection mechanism is located behind the two cutting drums to collect the slag conveyed between the two cutting drums. Attached Figure Description

[0038] Figure 1 This is a front view of Embodiment 1 of the tunnel boring machine main unit of the present invention;

[0039] Figure 2 for Figure 1 A magnified view of a portion of the image;

[0040] Figure 3 This is a side view of the two-sided excavation mechanism in Embodiment 1 of the tunnel boring machine main unit of the present invention;

[0041] Figure 4 for Figure 3 A magnified view of a portion of the image;

[0042] Figure 5 This is a diagram showing the usage status of the front telescopic shield and the rear telescopic shield in Embodiment 1 of the tunnel boring machine of the present invention (the front telescopic shield is in the state of extending the front shield backward).

[0043] Figure 6 This is a diagram showing the usage status of the front telescopic shield and the rear telescopic shield in Embodiment 1 of the tunnel boring machine of the present invention (the front telescopic shield is in the forward retraction state).

[0044] Figure 7 This is a side view of the front telescopic shield and the rear telescopic shield in Embodiment 1 of the tunnel boring machine main unit of the present invention;

[0045] Figure 8 This is a side view of the bottom excavation mechanism in Embodiment 1 of the tunnel boring machine of the present invention;

[0046] Figure 9 This is a diagram illustrating the excavation process of the widening device in Embodiment 1 of the tunnel boring machine of the present invention;

[0047] Figure 10 To and Figure 9 The tunnel cross-section diagrams corresponding to the excavation process;

[0048] Figure 11 This is a front view of embodiment 2 of the tunnel boring machine main unit of the present invention;

[0049] Figure 12 for Figure 11 A magnified view of a portion of the image;

[0050] Figure 13 This is a side view of the rear shield and rear telescopic shield in Embodiment 3 of the tunnel boring machine main unit of the present invention.

[0051] In the diagram: 1. Cutterhead; 2. Main beam; 2-1. First wear-resistant plate; 3. Mounting base; 3-1. Ring body; 3-2. Front stop body; 3-3. Rear stop body; 3-4. Second wear-resistant plate; 3-5. Connecting rod; 3-6. Sleeve body; 3-7. Connecting plate; 4. Drive cylinder; 5. Main drive; 6. Telescopic excavator arm; 6-1. Guide protrusion; 7. Rock breaking drum; 8. Rotary cylinder; 9. Connecting arm; 10. Telescopic arm; 11. Excavation drum; 12. Front shield; 13. Rear shield; 14. Front telescopic shield; 15. Front telescopic cylinder; 16. Rear telescopic shield; 17. Rear telescopic cylinder; 18. Star wheel slag collection mechanism; 19. Belt conveyor; 20. Support shoe; 21. Propulsion cylinder; 22. Fixed ring; 23. Rotary ring; 24. Gear ring; 25. Motor; 26. Drive gear. Detailed Implementation

[0052] To address the technical problems existing in the prior art, the basic concept of this invention is to add a front telescopic shield to the front shield and a rear telescopic shield to the rear shield, or the rear shield itself is a rear telescopic shield that can move back and forth relative to the main beam. Both the front and rear telescopic shields include multiple sub-shields. When it is necessary to widen the circular cross-section tunnel, one of the sub-shields of the front telescopic shield retracts forward, exposing a small section of the circular cross-section tunnel. After widening, the corresponding sub-shield of the rear telescopic shield extends forward to support the irregular cross-section tunnel in a timely manner, ensuring that both the un-widened and widened tunnel walls are in a supported state.

[0053] The features and performance of the present invention will be further described in detail below with reference to embodiments.

[0054] Embodiment 1 of the tunnel boring machine main unit in this invention:

[0055] like Figure 1 As shown, the tunnel boring machine (TBM) main unit includes a cutterhead 1 for excavating a circular cross-section tunnel and a front shield 12 for supporting the circular cross-section tunnel. It also includes a main drive 5 for driving the cutterhead 1 to rotate, and a main beam 2 extending forward and backward. Support shoes 20 are mounted on the main beam 2, and a propulsion cylinder 21 connects the support shoes 20 to the main beam 2. The main beam 2 is also equipped with an enlargement device for enlarging the circular cross-section tunnel excavated by the cutterhead 1 to form an irregular cross-section tunnel. In this embodiment, the irregular cross-section is a horseshoe-shaped cross-section. The TBM main unit also includes a rear shield 13 for supporting the horseshoe-shaped cross-section tunnel. The rear shield 13 is connected to the main beam 2 via a bracket and is fixed relative to the main beam 2. When the cutterhead 1 advances forward, the rear shield 13 moves forward with the main beam 2.

[0056] Combination Figure 2 , Figure 5 , Figure 6 and Figure 7 As shown, the front shield 12 is equipped with a front telescopic shield 14 that can extend backward and retract forward, and the rear shield 13 is equipped with a rear telescopic shield 16 that can extend forward and retract backward. The front telescopic shield 14 is an arc-shaped shield body, and the shape of the rear telescopic shield 16 is adapted to a horseshoe-shaped cross-section. Both the front telescopic shield 14 and the rear telescopic shield 16 include at least two circumferentially spaced sub-shields; in this embodiment, there are four sub-shields. Each sub-shield is equipped with an independent telescopic drive mechanism that can control the forward and backward movement of the sub-shield. In this embodiment, the telescopic drive mechanism configured for the sub-shield of the front telescopic shield 14 is a front telescopic hydraulic cylinder 15. One end of the front telescopic hydraulic cylinder 15 is connected to the sub-shield of the front telescopic shield 14, and the other end is connected to the front shield 12. The telescopic drive mechanism configured on the sub-shield of the rear telescopic shield 16 is a rear telescopic hydraulic cylinder 17. One end of the rear telescopic hydraulic cylinder 17 is connected to the sub-shield of the rear telescopic shield 16, and the other end is connected to the rear shield 13.

[0057] The front telescopic shield 14 and the rear telescopic shield 16 are aligned front and rear, allowing each section of the front telescopic shield 14 to extend rearward and support the circular tunnel as the cutterhead 1 excavates forward into the tunnel. When the circular tunnel needs to be enlarged, one section of the front telescopic shield 14 retracts forward, exposing a small section of the tunnel, while the other sections are supported by the remaining sections, significantly reducing construction risks. After the enlargement device excavates a small section of the horseshoe-shaped tunnel, the corresponding section of the rear telescopic shield 16 extends forward to support the horseshoe-shaped tunnel. Therefore, throughout the entire construction process, only the section of tunnel enlarged by the enlargement device is exposed; both the un-enlarged and enlarged tunnel walls are supported, greatly reducing safety risks and the probability of accidents.

[0058] In this invention, the excavation of the widening device and the cutterhead 1 can be carried out simultaneously to improve construction efficiency. When the widening device widens a small circular cross-section tunnel, the remaining sub-shields of the front telescopic shield 14, except for one sub-shield that has already retracted forward, can adaptively continue to extend backward to support the newly exposed circular cross-section tunnel. When the widening device widens the next location, the corresponding sub-shield of the front telescopic shield 14 needs to retract forward again. Simultaneously, during the excavation process of the cutterhead 1, because the rear shield 13 moves forward synchronously, each sub-shield of the rear telescopic shield 16 needs to retract backward to avoid jamming. After a small horseshoe-shaped cross-section tunnel is widened, the corresponding sub-shield of the rear telescopic shield 16 needs to extend forward again for timely support. Therefore, the sub-shields of the front telescopic shield 14 and the rear telescopic shield 16 are in a state of continuous forward and backward movement to adapt to the excavation process of the cutterhead 1 and the widening device, achieving perfect speed matching and ensuring geological stability.

[0059] Furthermore, the rear shield 13 has a sandwich structure with the same shape as the rear shield 13. Each sub-shield of the rear telescopic shield 16 is set within the sandwich structure of the rear shield 13. This not only provides protection but also ensures that the rear telescopic shield 16 is close enough to the tunnel wall to enhance its support effect. Similarly, the front shield 12 has a sandwich structure with the same shape as the front shield 12. Each sub-shield of the front telescopic shield 14 is set within the sandwich structure of the front shield 12. This also not only provides protection but also ensures that the front telescopic shield 14 is close enough to the tunnel wall to enhance its support effect.

[0060] The aforementioned widening excavation device includes widening excavation mechanisms on both sides, specifically, such as... Figure 1 and Figure 2As shown, the excavation device includes a mounting base 3 that is guided and installed on the main beam 2 in the front-back direction. The mounting base 3 is connected to a telescopic drive device for driving the mounting base 3 to move back and forth. In this embodiment, the telescopic drive device is specifically a drive cylinder 4. Multiple drive cylinders 4 are arranged in the circumferential direction. The drive cylinder 4 is located on the front side of the mounting base 3, with one end connected to the mounting base 3 and the other end connected to the main drive 5.

[0061] The mounting base 3 is equipped with a telescopic excavator arm 6, whose rotation axis extends forward and backward via a rotary drive structure. "Telescopic" means the excavator arm can extend and retract; for example, two arm sections are nested together and each contains a built-in hydraulic cylinder. The cylinders are connected to the two arm sections at their respective ends, allowing control of one arm section's extension or retraction, thus changing the length of the telescopic excavator arm. The telescopic excavator arm 6 is perpendicular to the main beam 2 and its end is connected to a rock-breaking device. In this embodiment, the rock-breaking device is a rock-breaking roller 7, which is equipped with cutting teeth. The rotation axis of the rock-breaking roller 7 is perpendicular to the forward and backward direction.

[0062] Combination Figure 2 and Figure 3 As shown, the mounting base 3 includes a ring 3-1 sleeved on the outside of the main beam 2. Since the cross-section of the main beam 2 is rectangular, the inner hole of the ring 3-1 is a rectangular hole, and a first wear-resistant plate 2-1 is fixed at each of the four corners of the main beam 2. Figure 4 As shown in the figure, the first wear-resistant plate 2-1 contacts the inner wall of the ring 3-1, which can reduce the friction when the mounting base 3 moves back and forth.

[0063] The outer circumference of the ring 3-1 is entirely cylindrical. The front end of the ring 3-1 is provided with a front stop 3-2 and the rear end is provided with a rear stop 3-3. The front stop 3-2 is connected to one end of the drive cylinder 4. The end of the telescopic excavation arm 6 is clamped between the front stop 3-2 and the rear stop 3-3 and fits against the cylindrical surface of the ring 3-1 through an arc surface. A telescopic driver is connected between the telescopic excavation arm 6 and the mounting base 3 to drive the telescopic excavation arm 6 to rotate along the cylindrical surface of the ring 3-1. In this embodiment, the telescopic driver is a rotary cylinder 8. Such a rotary drive structure is relatively simple and convenient for processing, manufacturing and installation.

[0064] The telescopic excavating arm 6 and the rock-breaking roller 7 excavate from back to front under the control of the drive cylinder 4. During rock breaking, the telescopic excavating arm 6 experiences forces in the rearward and towards the main beam 2. Because the telescopic excavating arm 6 and the ring body 3-1 are in surface-to-surface contact, the mounting base 3 can withstand a relatively large reaction force. Simultaneously, in the direction perpendicular to the front-rear direction, the length of the rear stop 3-3 is greater than the length of the front stop 3-2, allowing the rear stop 3-3 to better withstand the reaction force during rock breaking. Furthermore, to reduce friction during the rotation of the telescopic excavating arm 6, a second wear-resistant plate 3-4 is provided on the rear stop 3-3, contacting the side of the telescopic excavating arm 6. In other embodiments, wear-resistant plates may only be provided on the front stop, or wear-resistant plates may be provided on both the front and rear stops.

[0065] In this embodiment, the telescopic excavating arms 6 are arranged in pairs, with the two telescopic excavating arms 6 in a pair located on the left and right sides of the main beam 2, respectively, which can improve excavation efficiency. Figure 3 As shown, each telescopic excavator arm 6 is connected to a rock-breaking roller 7 at its end, and each telescopic excavator arm 6 is connected to a rotary cylinder 8 between itself and the mounting base 3. A connecting rod 3-5 is fixed on the mounting base 3. One end of the two rotary cylinders 8 corresponding to a pair of telescopic excavator arms 6 is hinged to the connecting rod 3-5 through the same pin, which makes the structure relatively compact. Figure 3 The image shows a pair of telescopic excavation arms 6. If the stroke of the rotary cylinder 8 is insufficient to allow the rock-breaking roller 7 to excavate to the bottom of the tunnel, another pair of telescopic excavation arms can be added below the mounting base 3.

[0066] Although the telescopic excavator arm 6 is clamped between the front stop 3-2 and the rear stop 3-3 and is in close contact with the surface of the ring 3-1, the telescopic excavator arm 6 will not detach from the mounting base 3 under the force of the rotary cylinder 8. However, to improve its rotational stability, especially when a pair of telescopic excavator arms are also provided below, and to prevent the telescopic excavator arms from detaching, a guide structure is provided at the end of the telescopic excavator arm 6 to guide and cooperate with the rear stop 3-3 in the circumferential direction. Figure 2 As shown, the guiding structure is a guide protrusion 6-1 located on the rear side of the end of the telescopic excavator arm 6. The guide protrusion 6-1 is arc-shaped and extends into the annular groove between the second wear-resistant plate 3-4 and the ring body 3-1, respectively contacting and slidingly engaging with the second wear-resistant plate 3-4 and the ring body 3-1, thereby preventing the telescopic excavator arm 6 from coming off. Of course, in other embodiments, an annular groove can also be provided on the front stop body 3-2. In this case, the guide protrusion is only provided on the front side of the end of the telescopic excavator arm 6, and the guide protrusion extends into the annular groove. Alternatively, guide protrusions can be provided on both the front and rear sides of the end of the telescopic excavator arm 6. In this case, the front stop body 3-2 and the rear stop body 3-3 are respectively provided with annular grooves for the guide protrusions to extend into.

[0067] like Figure 1and Figure 8 As shown, the excavation device also includes a bottom excavation mechanism connected to the lower part of the mounting base 3 for excavating the bottom of the tunnel. When the drive cylinder 4 controls the telescopic excavation arm 6 and the rock-breaking drum 7 to move forward for excavation, the bottom excavation mechanism moves forward synchronously with the mounting base 3, preventing the rock-breaking drum 7 from reaching the bottom of the tunnel for excavation. Specifically, the bottom excavation mechanism includes a connecting arm 9 connected to the mounting base 3. The connecting arm 9 includes a left-right extending arm body, and the left and right ends of the arm body are respectively provided with downwardly extending extension arms. The extension arms are connected to telescopic arms 10 that can extend and retract vertically via cylinders. The ends of the two telescopic arms 10 are respectively connected to excavation drums 11. The two excavation drums 11 are arranged symmetrically from left to right, which can excavate the lower outline of the horseshoe-shaped cross-section tunnel.

[0068] Furthermore, both excavating drums 11 are cutting drums equipped with cutting teeth, which are arranged in a spiral pattern to transport the excavated rock towards the center. This achieves both excavation and rock transport, making construction more convenient. In addition, the tunnel boring machine (TBM) main unit also includes a star wheel rock collection mechanism 18 connected to the lower part of the main beam 2. The star wheel rock collection mechanism 18 is located behind the two cutting drums to collect the rock transported towards the center, facilitating its rearward transport. A belt conveyor 19 is installed behind the star wheel rock collection mechanism 18 to facilitate the transport of the rock out of the tunnel.

[0069] In this embodiment, the construction process of the tunnel boring machine host is as follows:

[0070] After the cutterhead 1 excavates a circular cross-section tunnel, the two rock-breaking rollers 7, under the control of the rotary cylinder 8, first rotate to the lower part of the tunnel, and then move forward under the control of the drive cylinder 4 to widen the excavation. Figure 9 As shown in (a) above, the excavated cross-section is as follows: Figure 10 As shown in (a) of the diagram. For this location, the depth of a single excavation is insufficient to achieve the horseshoe-shaped cross-section and dimensions. Therefore, two more excavations are required. First, the telescopic excavating arm 6 is moved backward and reset by controlling the drive cylinder 4. Then, the telescopic excavating arm 6 is extended, causing the rock-breaking roller 7 to move outward. Then, the second excavation is performed, as shown in (a). Figure 9 As shown in (b) above, the excavated cross-section is as follows: Figure 10 As shown in (b) above. Then repeat the above steps to perform a third excavation, as shown in [example]. Figure 9 As shown in (c), the excavated cross-section is as follows: Figure 10As shown in (c) in the diagram. During the third expansion excavation process, the two excavating rollers 11 also extend to expand the tunnel bottom. Of course, since the excavating rollers 11 move forward synchronously with the mounting base 3 and the connecting arm 9 is connected to the rear side of the mounting base 3, the excavating rollers 11 and the rock-breaking roller 7 are not in the same cross section, and the two will not interfere with each other. Therefore, when the rock-breaking roller 7 starts to expand the tunnel, the excavating rollers 11 can extend to expand the tunnel bottom, and the expansion is also carried out in multiple stages.

[0071] Once the excavation depth at one of the bottom locations is deemed acceptable, the telescopic excavation arm 6 and the rock-breaking roller 7 are rotated to the top of the tunnel via the rotary cylinder 8 to perform further excavation at the top location. Figure 9 As shown in (d) in the figure, the excavated cross section is as follows: Figure 10 As shown in (d), since the depth of the top excavation is relatively shallow, it can be completed in one go. Then, the telescopic excavation arm 6 is rotated to the side by the rotary cylinder 8 to continue the excavation, as shown in (d). Figure 9 As shown in (e) in the figure, the excavated cross section is as follows Figure 10 As shown in (e), this location can also be excavated in one go. Then, the telescopic excavation arm 6 is rotated by the rotary cylinder 8 to excavate the next location, as shown in the diagram. Figure 9 As shown in (f), the excavated cross-section is as follows: Figure 10 As shown in (f), because the thickness at this location is relatively high, it is excavated in two stages, as follows: Figure 9 As shown in (g) in the figure, the completed cross-section is as follows: Figure 10 As shown in (g). Then, the telescopic excavator arm 6 is rotated by the rotary cylinder 8 to further expand the excavation at the last position, as shown in (g). Figure 9 As shown in (h), the excavated cross-section is as follows: Figure 10 As shown in (h), because the thickness at this location is relatively high, it is also excavated in two stages, as follows. Figure 9 As shown in (i), the completed cross-section is as follows Figure 10 As shown in (i), the excavation of the horseshoe-shaped tunnel is now complete.

[0072] During the excavation process of the rock-breaking drum 7, the two excavating drums 11 can gather the falling debris towards the center, and then transport it to the belt conveyor 19 via the star wheel debris collection mechanism 18, and finally transport it out of the tunnel. Additionally, when the rock-breaking drum 7 excavates to the position supported by the front telescopic shield 14, the corresponding sub-shield retracts forward to expose a small circular section of the tunnel. After the widening excavation is completed, a corresponding sub-shield on the rear telescopic shield 16 extends forward for support. Of course, the widening excavation sequence of the rock-breaking drum 7 is not limited to the above process; for example, the top of the tunnel can be widened first, then the sides, and finally the bottom.

[0073] In this invention, the telescopic excavation arm is perpendicular to the main beam, and the telescopic excavation arm excavates in a posture perpendicular to the tunnel without occupying too much space in the length direction. Therefore, the length of the main beam can be shortened, making the structure of the tunneling machine host more compact and the length dimension smaller, thus improving the turning performance.

[0074] Embodiment 2 of the tunnel boring machine main unit in this invention:

[0075] like Figure 11 and Figure 12 As shown, the difference between this embodiment and Embodiment 1 lies in the structure of the rotary drive structure and the mounting base 3. In Embodiment 2, the mounting base 3 includes a sleeve 3-6 that is guided and sleeved outside the main beam 2, and a connecting plate 3-7 fixed to the front end of the sleeve 3-6. The connecting plate 3-7 is connected to one end of the drive cylinder 4. The rotary drive structure includes a rotary bearing, which includes a fixed ring 22 fixed relative to the sleeve 3-6 and a rotary ring 23 that can rotate relative to the sleeve 3-6 and whose rotation axis extends back and forth. The telescopic excavator arm 6 is fixed on the rotary ring 23. A gear ring 24 is provided on the rotary ring 23. The rotary drive structure also includes a rotary power source and a drive gear 26 installed at the output end of the rotary power source. The rotary power source is a motor 25 fixed on the fixed ring 22, which is used to control the rotation of the drive gear 26. The drive gear 26 meshes with the gear ring 24, which can drive the rotary ring 23 to rotate, thereby changing the circumferential position of the telescopic excavator arm 6 and the rock-breaking drum 7. The other structures and excavation process are the same as in Example 1, and will not be repeated in this example.

[0076] Embodiment 3 of the tunnel boring machine main unit in this invention:

[0077] This embodiment differs from Embodiments 1 and 2 in that, as Figure 13 As shown, the rear shield 13 has an arc-shaped sandwich structure. Each of the sub-shields of the rear telescopic shield 16 is arc-shaped and is set in the sandwich of the rear shield 13. Although the gap between the rear telescopic shield 16 and the tunnel wall is relatively large at this time, it can still play a supporting role.

[0078] In other embodiments of the tunnel boring machine main unit: instead of installing a rear telescopic shield on the rear shield, the rear shield is set as a telescopic shield that can move back and forth relative to the main beam. Of course, the telescopic shield still includes multiple sub-shields. At this time, multiple sliding blocks can be installed on the main beam in a front-to-back guide manner. Each sliding block is connected to a sub-shield through a bracket. At the same time, a telescopic drive mechanism is connected between the main beam and each sliding block to control the front-to-back movement of each sliding block and sub-shield individually. The timing of the sub-shield movement is the same as above.

[0079] In other embodiments of the tunnel boring machine main unit: the hydraulic cylinders controlling the forward and backward telescopic movement of each sub-shield of the front telescopic shield and the rear telescopic shield can also be replaced with pneumatic cylinders.

[0080] In other embodiments of the tunnel boring machine main unit: the front telescopic shield and the rear telescopic shield can also be two or three sections. Of course, depending on the tunnel diameter and the performance of the excavation device, it can also be set to five sections or more.

[0081] In other embodiments of the tunnel boring machine main unit: the individual shields of the front telescopic shield may not be installed in the interlayer of the front shield, but are located on the inner side of the front shield, close to the inner wall of the front shield. Similarly, the individual shields of the rear telescopic shield may not be installed in the interlayer of the rear shield, but are located on the inner side of the rear shield, close to the inner wall of the rear shield.

[0082] In other embodiments of the tunnel boring machine main unit: the star wheel muck collection mechanism can also be replaced by a muck-loading robot, which scoops the muck onto the belt conveyor. Of course, if the belt conveyor is set relatively high, a lifting chain bucket can also be set, where the muck-loading robot first scoops the muck into the chain bucket, and then lifts and dumps it onto the belt conveyor.

[0083] In other embodiments of the tunnel boring machine main unit: the cutting tool on the excavation drum can also be a hob, in which case the excavation drum is equivalent to a wheel cutterhead. Of course, the cutting tool on the excavation drum can also be a scraper. In other embodiments, the excavation drum can also be replaced by a cutting head.

[0084] In other embodiments of the tunnel boring machine main unit: the cutting tools on the two excavation drums may not be arranged in a spiral shape. In this case, the excavation drums do not have the function of conveying slag, so it is necessary to connect a slag removal robot to the main beam to convey the slag backward.

[0085] In other embodiments of the tunnel boring machine main unit: the excavation device may not include the bottom excavation mechanism, that is, the connecting arm, telescopic arm and excavation drum are no longer set. In this case, only the rock breaking drum is used to rotate to both sides of the bottom of the tunnel for excavation.

[0086] In other embodiments of the tunnel boring machine main unit: when the power is sufficient, the telescopic drive device that controls the forward and backward movement of the mounting base can be replaced with a cylinder.

[0087] In other embodiments of the tunnel boring machine main unit: the cutting teeth on the rock breaking drum can also be replaced with roller cutters, in which case the rock breaking drum is equivalent to a wheel cutterhead.

[0088] In other embodiments of the tunnel boring machine main unit: the rock breaking device can be a cutting head or a rock breaking drum whose own rotation axis extends in the front-to-back direction. In this case, the telescopic excavation arm is driven to rotate circumferentially by the rotary drive structure, so that the rock breaking device can expand the circular cross-section tunnel. During the expansion process, the rock breaking device can be moved outward by extending the telescopic excavation arm, thereby controlling the excavation depth and cross-sectional shape. After the cross-section is excavated, the rock breaking device is retracted inward by retracting the telescopic excavation arm. Then, the mounting base and the telescopic excavation arm are moved forward by the telescopic drive device, so that the rock breaking device moves to the next excavation position. The above process can be repeated.

[0089] In other embodiments of the tunnel boring machine main unit: the telescopic drive device can also be located on the rear side of the mounting base, in which case the telescopic drive device is connected between the mounting base and the main beam.

[0090] In other embodiments of the tunnel boring machine main unit: Unlike embodiment 2, the rotational power source can be a hydraulic motor, and the gear ring can also be set on the fixed ring, in which case the rotational power source is fixed on the rotating ring.

[0091] In other embodiments of the tunnel boring machine main unit: Unlike embodiment 1, the telescopic actuator that controls the rotation of the telescopic excavation arm can also be a cylinder, provided that there is sufficient power.

[0092] In other embodiments of the tunnel boring machine host: only one telescopic excavation arm can be set, and in this case there is also only one rock breaking device.

[0093] In other embodiments of the tunnel boring machine main unit: Unlike embodiment 1, the guide structure at the end of the telescopic excavator arm is a guide groove. In this case, the rear stop and / or the front stop are provided with annular protrusions extending into the guide groove to guide the circumferential rotation of the telescopic excavator arm and prevent the telescopic excavator arm from coming off.

[0094] In other embodiments of the tunnel boring machine main unit: Unlike embodiment 1, the end of the telescopic excavator arm is no longer provided with a guide structure, and the telescopic excavator arm is held on the mounting base by the telescopic drive alone.

[0095] In other embodiments of the tunnel boring machine main unit: Unlike embodiment 1, wear-resistant plates may no longer be provided on the rear stop and / or the front stop. In this case, the side of the telescopic excavation arm directly contacts the front stop and the rear stop.

[0096] In other embodiments of the tunnel boring machine main unit: Unlike embodiment 1, regardless of whether the excavation direction of the rock breaking device is from back to front or circumferential rotation, the length of the rear stop can be equal to the length of the front stop.

[0097] In other embodiments of the tunnel boring machine host: Unlike embodiment 1, only the outer peripheral surface of the ring body of the mounting base can be set as a cylindrical surface, as long as it can meet the rotation stroke of the telescopic excavation arm.

[0098] In other embodiments of the tunnel boring machine host: the irregular cross-section tunnel can also be a tunnel with a similar rectangular cross-section. By controlling the angle and elongation of the rock breaking device, the excavation of other irregular cross-section tunnels can be achieved.

[0099] The embodiment of the tunnel boring machine in this invention is as follows: The tunnel boring machine includes a main unit and supporting equipment. The structure of the main unit is the same as any embodiment of the tunnel boring machine main unit described above, and will not be repeated here.

[0100] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. A tunnel boring machine (TBM) main unit, comprising a cutterhead for excavating a circular cross-section tunnel, a front shield for supporting the circular cross-section tunnel, an enlargement device for enlarging the circular cross-section tunnel to form an irregular cross-section tunnel, and a rear shield for supporting the irregular cross-section tunnel, characterized in that, The front shield is equipped with a front telescopic shield that can extend backward and retract forward, and the rear shield is equipped with a rear telescopic shield that can extend forward and retract backward. Both the front and rear telescopic shields include at least two circumferentially spaced sub-shields. Each sub-shield is equipped with an independent telescopic drive mechanism that controls its forward and backward movement. The sub-shields of the front telescopic shield correspond to the sub-shields of the rear telescopic shield. During the excavation of a circular cross-section tunnel by the cutterhead, each sub-shield of the front telescopic shield extends backward to support the circular cross-section tunnel. When it is necessary to enlarge the circular cross-section tunnel, one of the sub-shields of the front telescopic shield retracts forward, exposing a small section of the circular cross-section tunnel, while the other sections are supported by the other sub-shields of the front telescopic shield. After the enlargement device excavates a small section of irregular cross-section tunnel, the corresponding sub-shield of the rear telescopic shield extends forward to support the irregular cross-section tunnel in a timely manner.

2. The tunnel boring machine main unit according to claim 1, characterized in that, The rear shield is fixedly installed relative to the main beam of the tunnel boring machine host. The rear telescopic shield is installed on the rear shield. The rear shield has a sandwich structure with the same shape as the rear shield. Each sub-shield of the rear telescopic shield is set in the sandwich of the rear shield.

3. The tunnel boring machine main unit according to claim 1, characterized in that, The rear shield is fixed relative to the main beam of the tunnel boring machine host. The rear telescopic shield is installed on the rear shield. The rear shield has an arc-shaped sandwich structure. Each sub-shield of the rear telescopic shield is arc-shaped and is set in the sandwich of the rear shield.

4. The tunnel boring machine main unit according to any one of claims 1 to 3, characterized in that, The front shield has a sandwich structure that matches the shape of the front shield, and each of the sub-shields of the front telescopic shield is set inside the sandwich of the front shield.

5. The tunnel boring machine main unit according to any one of claims 1 to 3, characterized in that, The excavation device includes a mounting base that is guided and installed on the main beam of the tunnel boring machine host in the front-to-back direction. The mounting base is connected to a telescopic drive device for driving the mounting base to move back and forth. A rotatable telescopic excavating arm is installed on the mounting base. A rotary drive structure for driving the telescopic excavating arm to rotate is provided between the telescopic excavating arm and the mounting base. The rotation axis of the telescopic excavating arm extends front and back. The telescopic excavating arm is perpendicular to the main beam and its end is connected to a rock breaking device.

6. The tunnel boring machine main unit according to claim 5, characterized in that, The mounting base includes a ring body fitted around the outside of the main beam. At least part of the outer circumferential surface of the ring body is cylindrical. A front stop is provided at the front end of the ring body and a rear stop is provided at the rear end. The end of the telescopic excavator arm is clamped between the front stop and the rear stop and fits against the cylindrical surface of the ring body through an arc surface. A telescopic actuator for driving the telescopic excavator arm to rotate along the cylindrical surface of the ring body is connected between the telescopic excavator arm and the mounting base.

7. The tunnel boring machine main unit according to claim 6, characterized in that, The excavation direction of the rock breaking device is from back to front. In the direction perpendicular to the front-back direction, the length of the rear stop is greater than the length of the front stop.

8. The tunnel boring machine main unit according to claim 6, characterized in that, The rear stop and / or the front stop are provided with wear-resistant plates that contact the side of the telescopic excavator arm.

9. The tunnel boring machine main unit according to claim 6, characterized in that, The end of the telescopic excavator arm is provided with a guide structure that guides and cooperates with the rear stop and / or the front stop in the circumferential direction.

10. The tunnel boring machine main unit according to claim 6, characterized in that, The telescopic excavating arms are arranged in pairs, with the two telescopic excavating arms in a pair located on the left and right sides of the main beam, respectively. Each telescopic excavating arm is connected to a rock breaking device at its end, and each telescopic excavating arm is connected to a telescopic actuator between itself and the mounting base. One end of the two telescopic actuators corresponding to a pair of telescopic excavating arms is hinged to the mounting base through the same pin.

11. The tunnel boring machine main unit according to claim 5, characterized in that, The rotary drive structure includes a rotary bearing, which includes a fixed ring fixed relative to the mounting base and a rotary ring that can rotate relative to the mounting base and whose rotation axis extends back and forth. A gear ring is provided on the fixed ring or the rotary ring. The rotary drive structure also includes a rotary power source and a drive gear installed at the output end of the rotary power source. The drive gear meshes with the gear ring, and the telescopic excavator arm is fixed on the rotary ring.

12. The tunnel boring machine main unit according to claim 5, characterized in that, The excavation device also includes a bottom excavation mechanism connected to the lower part of the mounting base and used for excavating the bottom of the tunnel. The bottom excavation mechanism includes a connecting arm connected to the mounting base, and telescopic arms that can extend and retract vertically are connected to the left and right ends of the connecting arm, and excavation rollers are connected to the ends of the two telescopic arms respectively.

13. The tunnel boring machine main unit according to claim 12, characterized in that, The two excavating drums are arranged symmetrically on the left and right, and the cutting tools on both drums are arranged in a spiral shape to transport the excavated slag towards the center.

14. The tunnel boring machine main unit according to claim 13, characterized in that, The tunnel boring machine also includes a star wheel slag collection mechanism connected to the lower part of the main beam. The star wheel slag collection mechanism is located behind the two cutting drums to collect the slag conveyed from the two cutting drums to the middle.

15. A tunnel boring machine, comprising a main unit and supporting equipment, characterized in that, The main unit includes a cutterhead for excavating a circular cross-section tunnel, a front shield for supporting the circular cross-section tunnel, an enlargement device for enlarging the circular cross-section tunnel to form an irregular cross-section tunnel, and a rear shield for supporting the irregular cross-section tunnel. Its distinguishing feature is that the front shield is equipped with a front telescopic shield that can extend rearward and retract forward, and the rear shield is equipped with a rear telescopic shield that can extend forward and retract backward. Both the front and rear telescopic shields include at least two circumferentially spaced sub-shields, each sub-shield being equipped with an independent mechanism to control its forward and backward movement. The telescopic drive mechanism has the front telescopic shield's sub-shields corresponding to the rear telescopic shield's sub-shields. During the process of the cutterhead excavating a circular cross-section tunnel, each sub-shield of the front telescopic shield extends backward to support the circular cross-section tunnel. When it is necessary to enlarge the circular cross-section tunnel, one of the sub-shields of the front telescopic shield retracts forward, exposing a small section of the circular cross-section tunnel, while the other sections are supported by the other sub-shields of the front telescopic shield. After the enlargement device excavates a small section of irregular cross-section tunnel, the corresponding sub-shield of the rear telescopic shield extends forward to support the irregular cross-section tunnel in a timely manner.

16. The tunnel boring machine according to claim 15, characterized in that, The rear shield is fixed relative to the main beam of the host machine. The rear telescopic shield is installed on the rear shield. The rear shield has a sandwich structure with the same shape as the rear shield. Each sub-shield of the rear telescopic shield is set in the sandwich of the rear shield.

17. The tunnel boring machine according to claim 15, characterized in that, The rear shield is fixed relative to the main beam of the host machine. The rear telescopic shield is installed on the rear shield. The rear shield has an arc-shaped sandwich structure. Each sub-shield of the rear telescopic shield is arc-shaped and is set in the sandwich of the rear shield.

18. The tunnel boring machine according to any one of claims 15 to 17, characterized in that, The front shield has a sandwich structure that matches the shape of the front shield, and each of the sub-shields of the front telescopic shield is set inside the sandwich of the front shield.

19. The tunnel boring machine according to any one of claims 15 to 17, characterized in that, The excavation device includes a mounting base that is guided and installed on the main beam of the tunnel boring machine host in the front-to-back direction. The mounting base is connected to a telescopic drive device for driving the mounting base to move back and forth. A rotatable telescopic excavating arm is installed on the mounting base. A rotary drive structure for driving the telescopic excavating arm to rotate is provided between the telescopic excavating arm and the mounting base. The rotation axis of the telescopic excavating arm extends front and back. The telescopic excavating arm is perpendicular to the main beam and its end is connected to a rock breaking device.

20. The tunnel boring machine according to claim 19, characterized in that, The mounting base includes a ring body fitted around the outside of the main beam. At least part of the outer circumferential surface of the ring body is cylindrical. A front stop is provided at the front end of the ring body and a rear stop is provided at the rear end. The end of the telescopic excavator arm is clamped between the front stop and the rear stop and fits against the cylindrical surface of the ring body through an arc surface. A telescopic actuator for driving the telescopic excavator arm to rotate along the cylindrical surface of the ring body is connected between the telescopic excavator arm and the mounting base.

21. The tunnel boring machine according to claim 20, characterized in that, The excavation direction of the rock breaking device is from back to front. In the direction perpendicular to the front-back direction, the length of the rear stop is greater than the length of the front stop.

22. The tunnel boring machine according to claim 20, characterized in that, The rear stop and / or the front stop are provided with wear-resistant plates that contact the side of the telescopic excavator arm.

23. The tunnel boring machine according to claim 20, characterized in that, The end of the telescopic excavator arm is provided with a guide structure that guides and cooperates with the rear stop and / or the front stop in the circumferential direction.

24. The tunnel boring machine according to claim 20, characterized in that, The telescopic excavating arms are arranged in pairs, with the two telescopic excavating arms in a pair located on the left and right sides of the main beam, respectively. Each telescopic excavating arm is connected to a rock breaking device at its end, and each telescopic excavating arm is connected to a telescopic actuator between itself and the mounting base. One end of the two telescopic actuators corresponding to a pair of telescopic excavating arms is hinged to the mounting base through the same pin.

25. The tunnel boring machine according to claim 19, characterized in that, The rotary drive structure includes a rotary bearing, which includes a fixed ring fixed relative to the mounting base and a rotary ring that can rotate relative to the mounting base and whose rotation axis extends back and forth. A gear ring is provided on the fixed ring or the rotary ring. The rotary drive structure also includes a rotary power source and a drive gear installed at the output end of the rotary power source. The drive gear meshes with the gear ring, and the telescopic excavator arm is fixed on the rotary ring.

26. The tunnel boring machine according to claim 19, characterized in that, The excavation device also includes a bottom excavation mechanism connected to the lower part of the mounting base and used for excavating the bottom of the tunnel. The bottom excavation mechanism includes a connecting arm connected to the mounting base, and telescopic arms that can extend and retract vertically are connected to the left and right ends of the connecting arm, and excavation rollers are connected to the ends of the two telescopic arms respectively.

27. The tunnel boring machine according to claim 26, characterized in that, The two excavating drums are arranged symmetrically on the left and right, and the cutting tools on both drums are arranged in a spiral shape to transport the excavated slag towards the center.

28. The tunnel boring machine according to claim 27, characterized in that, The main unit also includes a star wheel slag collection mechanism connected to the lower part of the main beam. The star wheel slag collection mechanism is located behind the two cutting drums to collect the slag conveyed between the two cutting drums.

Images