Tunnel boring machine

Abstract

By increasing the output efficiency of each cutter motor in operation, the overall power consumption of the cutter motors is reduced. [Solution] The tunnel boring machine 1 comprises a boring machine body 10, a cutter head 11 rotatably mounted at the front end of the boring machine body 10, a plurality of cutter motors 40 that generate rotational power for the cutter head 11, and a control device 110 that controls the number of operating cutter motors m, which is the number of cutter motors 40 that are operated out of the plurality of cutter motors 40, according to the excavation load when the cutter head 11 excavates the ground. The control device 110 reduces the number of operating motors m as the excavation load decreases, thereby operating only a portion of the plurality of cutter motors 40 and concentrating the load for generating rotational power on that portion of cutter motors 40.

Description

[Technical Field]

[0001] This invention relates to a tunnel boring machine. [Background technology]

[0002] Tunneling machines, such as shield machines, excavate tunnels by rotating a cutter head, with multiple cutter bits mounted on the front of the cutter head excavating the ground ahead and forming a tunnel face. Tunneling machines are equipped with various electric motors, including multiple cutter motors (cutter motors) to generate rotational power for the cutter head and multiple hydraulic motors to generate thrust for the shield jacks. In recent years, from an energy conservation perspective, there has been a demand to reduce the power consumption of these electric motors.

[0003] Patent Document 1 discloses adjusting the power consumed by a shield machine by adjusting the excavation speed of the shield machine according to the predicted power consumption, so that the power consumed by the shield machine does not exceed the contracted power. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2013-34297 [Overview of the project] [Problems that the invention aims to solve]

[0005] Incidentally, the prior art described in Patent Document 1 above does not directly control the power consumption of multiple cutter motors by controlling their operation / non-operation, but rather secondarily controls the power consumption of the entire shield machine by controlling the excavation speed of the shield machine. Therefore, it is presumed that during tunnel excavation, the power consumption of the entire shield machine is controlled by basically operating all of the multiple cutter motors mounted on the shield machine and adjusting the excavation speed according to the excavation load.

[0006] However, when excavating in relatively soft or shallow ground, where excavation resistance is low, operating all the cutter motors installed on the tunnel boring machine as in the conventional technology described above results in a problem where the load factor per operating cutter motor (the output efficiency of each motor relative to the supplied power) decreases.

[0007] In the first place, electric motors such as cutter motors cannot achieve 100% output efficiency, and some energy loss occurs. When an electric motor operates at a high load near its rated output, the ratio of energy loss to the motor's output is low, allowing it to operate at high energy efficiency. On the other hand, when an electric motor operates at a load considerably lower than its rated output, the ratio of energy loss to the motor's output becomes high, resulting in low energy efficiency. To prevent this decrease in energy efficiency, it is preferable for electric motors such as cutter motors to operate at a high load closer to their rated output.

[0008] For example, when the excavation route extends from near the ground surface to a large depth, consider the case where a large number of high-spec cutter motors and other equipment are installed on a tunnel boring machine in accordance with the large-depth excavation (high excavation load). In this case, when using the tunnel boring machine to excavate the ground near the ground surface (low excavation load), the excavation load becomes extremely low compared to the large-depth excavation, resulting in a strong sense of surplus (overspecification) of the equipment. In this situation, if all the cutter motors are operated to excavate the low-load ground at a shallow depth, each cutter motor will continue to operate at a relatively low output efficiency (e.g., 30% or less) with respect to the rated output, and the output efficiency of each operating cutter motor will deteriorate. As a result, the power consumption of the entire cutter motor cannot be sufficiently suppressed, and there is a problem of reduced energy efficiency.

[0009] Therefore, conventionally, there has been a demand for a technology that can suppress the power consumption of the entire cutter motor required for excavation by optimizing the number of operating cutter motors according to the excavation load and concentrating the load on some of the cutter motors to increase the output efficiency per operating cutter motor.

[0010] Therefore, the present invention has been made in view of the above conventional problems, and an object thereof is to suppress the power consumption of the entire cutter motor by increasing the output efficiency per operating cutter motor.

Means for Solving the Problems

[0011] In order to solve the above problems, according to one aspect of the present invention, An excavation machine body, A cutter head rotatably provided at the front end of the excavation machine body, A plurality of cutter motors that generate the rotational power of the cutter head, A control device that controls the number of operating cutter motors (operating number), which is the number of cutter motors to be operated among the plurality of cutter motors, according to the excavation load when excavating the ground with the cutter head, And comprising The control device reduces the number of operating units as the excavation load decreases, thereby operating only some of the multiple cutter motors and concentrating the load for generating the rotational power on those some cutter motors, thereby providing a tunnel boring machine.

[0012] The load factor R of one cutter motor in operation is expressed by the following equation (1), and the load factor R of all cutter motors in operation All However, if it is represented by the following formula (2), The control device is During the excavation of the ground by the tunnel boring machine, the excavation load is the load ratio R All The number of operating units m may be controlled accordingly. R = P / Pk / 100 ... (1) R All =(P×m) / (Pk×n) / 100 ···(2) R: Load percentage of one cutter motor [%] R All : Load percentage of all cutter motors [%] P: Power consumption per cutter motor in operation [W] Pk: Rated output [W] of one cutter motor m: Number of cutter motors in operation n: Total number of cutter motors

[0013] The control device is The load factor R of each cutter motor in operation is set to be outside the low-load region, which is below the first reference value. All The number of operating units m may be controlled accordingly.

[0014] The control device is The load factor R of each cutter motor in operation is set to fall within the high load range of a second reference value or higher, which is greater than the first reference value. All The number of operating units m may be controlled accordingly.

[0015] The system further includes multiple inverters that convert power from a power source and supply it to each of the cutter motors, The control device may also be configured to stop supplying power to the inverter connected to the cutter motor that is not being operated among the plurality of cutter motors.

[0016] A power transmission mechanism that connects the cutter head and the plurality of cutter motors, and transmits the rotational power generated by at least some of the plurality of cutter motors to the cutter head, A detachment mechanism for attaching and detaching each of the cutter motors to the power transmission mechanism, Furthermore, The aforementioned attachment / detachment mechanism is The cutter motor to be operated from among the multiple cutter motors is mounted on the power transmission mechanism. At least some of the cutter motors that are not in operation among the aforementioned plurality of cutter motors may be detached from the power transmission mechanism.

[0017] The aforementioned attachment / detachment mechanism is Some of the cutter motors that are not in operation are detached from the power transmission mechanism. Some of the cutter motors that are not being operated may be left attached to the power transmission mechanism. [Effects of the Invention]

[0018] According to the present invention, the overall power consumption of the cutter motors can be reduced by increasing the output efficiency of each cutter motor in operation. [Brief explanation of the drawing]

[0019] [Figure 1] This is a schematic cross-sectional view showing a tunnel boring machine according to one embodiment of the present invention. [Figure 2]This is a block diagram that organizes the types of electric motors provided in the tunnel boring machine according to the same embodiment. [Figure 3] This is a schematic diagram showing a control panel provided in a tunnel boring machine according to the same embodiment. [Figure 4] This is a schematic diagram showing the correlation between the excavation load and the power consumption of the cutter motor according to the same embodiment. [Figure 5] This is a schematic diagram showing the circuit configuration of the control system for the tunnel boring machine according to the same embodiment (during high-load operation). [Figure 6] This is a circuit diagram showing the circuit configuration (during low-load operation) of the control system for the tunnel boring machine according to the same embodiment. [Figure 7] This is a schematic diagram showing the attachment / detachment mechanism of the cutter motor according to the same embodiment. [Figure 8] This is a perspective view showing the attachment / detachment mechanism for the cutter motor according to the same embodiment. [Figure 9] This is a schematic diagram showing the operating state of multiple cutter motors arranged circumferentially within the excavator body of the tunnel boring machine according to the same embodiment. [Figure 10] This table shows the criteria for controlling the number of cutter motors in operation according to the same embodiment. [Modes for carrying out the invention]

[0020] Preferred embodiments of the present invention will be described in detail below with reference to the attached drawings. The dimensions, materials, and other specific numerical values ​​shown in these embodiments are merely illustrative to facilitate understanding of the invention and do not limit the present invention unless otherwise specified. In this specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals to avoid redundant explanations, and elements not directly related to the present invention are omitted from the illustrations.

[0021] [1. Overall configuration of a tunnel boring machine] First, with reference to Figure 1, the schematic configuration of a tunnel boring machine 1 according to one embodiment of the present invention will be described. Figure 1 is a schematic cross-sectional view showing the tunnel boring machine 1 according to this embodiment.

[0022] In the following explanation, the direction of travel of the tunnel boring machine 1 (the direction of tunnel extension toward the tunnel face) may be referred to as the front or front side, and the opposite direction of travel (the direction of tunnel extension toward the tunnel entrance) may be referred to as the rear or back side. Also, the axial, radial, and circumferential directions of the cylindrical tunnel boring machine 1 may simply be referred to as the axial, radial, and circumferential directions, respectively. The axial direction of the tunnel boring machine 1 corresponds to the front-to-back direction of the tunnel boring machine 1.

[0023] The tunnel boring machine 1 according to this embodiment is, for example, an earth pressure type (including a mud pressure type) shield boring machine (shield machine) capable of excavating ground containing soil layers. As shown in Figure 1, the tunnel boring machine 1 according to this embodiment comprises a cylindrical boring machine body 10, a disc-shaped cutter head 11, a partition wall 12 positioned behind the cutter head 11, and a cutter rotation shaft 13.

[0024] The cutter head 11 is a roughly disc-shaped rotating body provided at the front end of the excavator body 10. The front end of the cutter rotation shaft 13 is fitted into the center of the cutter head 11, and the cutter head 11 is pivotally supported so as to be rotatable around the cutter rotation shaft 13. The cutter rotation shaft 13 extends parallel to the axial direction (front-to-back direction) of the excavator body 10.

[0025] The cutter head 11 includes an outer ring 31, an inner ring 32, a cutter spoke 33, a center cutter 34, and a cutter bit 35.

[0026] Of these, the outer ring 31 forms the outer circumference of the cutter head 11, and the inner ring 32 is positioned inward from the outer ring 31 in the diameter direction of the cutter. In addition, multiple cutter spokes 33 are arranged radially on the front surface of the cutter head 11, centered on the cutter rotation axis 13. A center cutter 34 is mounted in the center of the front surface of the cutter head 11. Furthermore, numerous cutter bits 35 are mounted on the front surface of the cutter spokes 33.

[0027] Furthermore, the cutter head 11 has multiple soil passage sections formed between multiple components, including the outer ring 31, inner ring 32, multiple cutter spokes 33, and multiple auxiliary cutter spokes. The soil passage sections are gaps (openings) formed between multiple components, including multiple cutter spokes 33, which are arranged radially with spacing in the circumferential direction. These soil passage sections function as soil intake ports for taking in excavated soil generated when the cutter head 11 excavates the ground at the face into the excavator body 10 (into the chamber 17, which will be described later).

[0028] A partition wall 12 is positioned behind the cutter head 11 in the excavator body 10. The partition wall 12 is a disc-shaped wall positioned perpendicular to the tunnel extension direction, and its outer edge is attached to the inner surface 10a of the excavator body 10. The cutter head 11 and the partition wall 12 are positioned at a predetermined distance in the tunnel extension direction (the axial direction of the excavator body 10). Various equipment of the tunnel excavator 1 is positioned behind the partition wall 12, and the partition wall 12 isolates this equipment from the excavated soil generated at the tunnel face. An outlet 12a, which is an opening for discharging excavated soil, is formed at the bottom of the partition wall 12.

[0029] A cutter rotation shaft 13 is rotatably supported in the center of the bulkhead 12. Furthermore, a ring-shaped rotating ring 14 is rotatably supported on the bulkhead 12 around the cutter rotation shaft 13. Multiple connecting beams 15 are provided at predetermined intervals in the circumferential direction at the front of the rotating ring 14. The multiple connecting beams 15 connect the cutter head 11 and the rotating ring 14. The front ends of the connecting beams 15 are connected to the connection between the inner circumferential ring 32 and the cutter spokes 33 of the cutter head 11. On the other hand, an external-toothed ring gear 14a is provided at the rear of the rotating ring 14. The rotating ring 14 and the connecting beams 15 constitute a power transmission mechanism 16. The power transmission mechanism 16 connects the cutter head 11 and the cutter motor 40 and is a mechanism for transmitting the rotational power generated by the cutter motor 40 to the cutter head 11.

[0030] Behind the bulkhead 12, a cutter head drive device consisting of an electric motor, a reduction gear, a pinion, etc., is provided. For convenience, the cutter head drive device is referred to here as the cutter motor 40. The cutter motor 40 is an example of a drive device configuration that generates rotational power to rotate the cutter head 11. The drive gear 40a at the tip of the cutter motor 40 meshes with the ring gear 14a of the rotating ring 14. Although only one cutter motor 40 is shown in Figure 1 for the sake of explanation, multiple cutter motors 40 are installed. The multiple cutter motors 40 are arranged in parallel along the circumferential direction of the excavator body 10, with gaps between them.

[0031] By supplying power to the cutter motor 40 and driving it, the cutter motor 40 generates power (rotational force) to rotate the cutter head 11. The rotational force generated by the cutter motor 40 is transmitted from the drive gear 40a to the connecting beam 15 via the ring gear 14a and the rotating ring 14. This allows the cutter head 11 to rotate around the cutter rotation axis 13. As a result, the front surface of the rotating cutter head 11 can be pressed against the ground at the face of the tunnel, and the ground can be excavated. Excavation using the cutter head 11 forms a tunnel face excavation surface 2 at the face of the tunnel.

[0032] A chamber 17 is defined between the cutter head 11 and the partition wall 12. The chamber 17 is a roughly cylindrical space partitioned by the back of the cutter head 11, the front of the partition wall 12, and the inner circumferential surface 10a of the excavator body 10. Excavated soil generated during ground excavation by the cutter head 11 is taken into the chamber 17 through a soil passage (excavated soil intake port) formed in the cutter head 11. The chamber 17 functions as a space (chamber) for temporarily storing the excavated soil. The excavated soil taken into the chamber 17 is discharged from the chamber 17 into the screw conveyor 20, which will be described later, through an outlet 12a located at the bottom of the partition wall 12.

[0033] Furthermore, a beam 18 is provided on the rear side of the excavator body 10 beyond the bulkhead 12. Both ends of the beam 18 are attached to the inner circumferential surface 10a of the excavator body 10. An erector device (not shown) is provided on the back of the beam 18. The erector device is provided so as to be movable in the axial (front-rear direction), radial direction and circumferential direction of the excavator body 10. Such an erector device is capable of gripping the lining members, namely the segments S, and assembling the gripped segments S along the inner wall surface (tunnel wall) of the tunnel T.

[0034] Segment S is a ring-shaped piece with a curved shape that conforms to the inner wall surface of the excavated tunnel T. By driving the erector device, multiple segments S can be assembled into a ring shape along the circumferential direction of the tunnel. As a result, the inner wall surface of the tunnel T is lined with multiple segments S, preventing the collapse of the inner wall surface.

[0035] Furthermore, multiple shield jacks 19 are installed inside the excavator body 10, extending along the inner circumferential surface 10a of the excavator body 10 in the tunnel extension direction (front-to-back direction). The multiple shield jacks 19 are arranged side by side at predetermined intervals in the circumferential direction of the inner circumferential surface 10a. Each shield jack 19 has a drive rod 19a that can extend and retract in the front-to-back direction. The tip of this drive rod 19a faces the front end surface of the existing segment S. When the drive rod 19a is extended, the tip of the drive rod 19a comes into contact with the front end surface of the existing segment S.

[0036] The shield jack 19 is an example of a hydraulic actuator that generates a propulsive reaction force to move the excavator body 10 forward. Each shield jack 19 is connected to a hydraulic unit (not shown). The hydraulic unit is a device that supplies hydraulic pressure to the shield jack 19, which is a hydraulic actuator. By supplying hydraulic pressure to the shield jack 19 by the hydraulic unit, the shield jack 19 extends in the front-rear direction (axial direction).

[0037] By extending the drive rod 19a of the shield jack 19 toward the rear and pressing against the segment S, a propulsive reaction force can be applied to the excavator body 10. In other words, the propulsive reaction force generated when the shield jack 19 presses against the segment S allows the excavator body 10 to move forward.

[0038] The tunnel boring machine 1 shown in Figure 1 is a type of tunnel boring machine in which thrust is transmitted from the front end of the shield jack 19 to the boring machine body 10, but the tunnel boring machine according to the present invention is not limited to this example. For example, the tunnel boring machine according to the present invention may be a type of tunnel boring machine in which thrust is transmitted from the rear part of the shield jack 19 to the boring machine body 10. Furthermore, the tunnel boring machine according to the present invention may be a type of tunnel boring machine that has a folding function and is propelled by pushing the front body, or a type of tunnel boring machine that has a folding function and is propelled by pushing the rear body. Furthermore, the tunnel boring machine according to the present invention may be a tunnel boring machine in which the drive method of the cutter head 11 is a method other than the intermediate support method shown in Figure 1 (for example, a center shaft method, a central axis support method, or an outer circumference support method).

[0039] Furthermore, a screw conveyor 20 is provided on the rear side of the partition wall 12 inside the excavator body 10. The screw conveyor 20 comprises a screw blade 21, a cylindrical body 22, a soil discharge port 23, and a drive unit 25. The cylindrical body 22 of the screw conveyor 20 is inclined and positioned so as it moves upward towards the rear inside the excavator body 10. The opening at the front end of the cylindrical body 22 of the screw conveyor 20 is connected to the discharge port 12a of the partition wall 12. As a result, the internal space of the cylindrical body 22 of the screw conveyor 20 communicates with the chamber 17 through the discharge port 12a of the partition wall 12. The screw blade 21 is rotatably mounted inside the cylindrical body 22. The soil discharge port 23 is provided on the lower side of the rear circumferential surface of the cylindrical body 22. The soil discharge port 23 is an opening through which excavated soil transported to the rear side of the cylindrical body 22 by the screw blades 21 is discharged to the outside of the cylindrical body 22. A drive unit 25 for rotating the screw blades 21 is installed at the rear end of the cylindrical body 22. By rotating the screw blades 21 with the drive unit 25, the excavated soil stored in the chamber 17 can be taken into the screw conveyor 20, transported toward the rear of the excavator body 10, and discharged from the soil discharge port 23.

[0040] [2. Control System] Next, with reference to Figures 2 to 6, a control system for controlling various devices such as electric motors mounted on the tunnel boring machine 1 according to this embodiment will be described.

[0041] [2.1. Motor to be controlled] First, with reference to Figure 2, the types of electric motors controlled by the control system according to this embodiment will be explained. Figure 2 is a block diagram summarizing the types of electric motors provided in the tunnel boring machine 1 according to this embodiment.

[0042] As shown in Figure 2, the electric motors provided in the tunnel boring machine 1 according to this embodiment include a cutter motor and a hydraulic motor. The cutter motor and the hydraulic motor are each connected to a power supply 60 for the tunnel boring machine 1 and are driven by the power supplied from the power supply 60.

[0043] The cutter motor is an electric motor that generates rotational power to rotate the cutter head 11. The cutter motor includes the above-mentioned multiple cutter motors 40-1, 40-2, ... 40-n (hereinafter sometimes collectively referred to as "cutter motors 40"). Here, "n" represents the total number of cutter motors 40 installed in the tunnel boring machine 1. "n" is an integer of 2 or more. As described above, the n cutter motors 40 are installed inside the boring machine body 10 at predetermined intervals along the circumferential direction of the boring machine body 10.

[0044] "m" represents the number of cutter motors 40 in operation. The number of cutter motors 40 in operation, m, is the number of cutter motors 40 that are operating (i.e., driven) by receiving power from the power supply 60, out of the n (total number) cutter motors 40 installed in the tunnel boring machine 1. "m" is an integer between 0 and n, inclusive. Operation means that the cutter motors 40 are in an operating state in which they receive power and are driven, generating rotational power for the cutter head 11.

[0045] In the tunnel boring machine 1 according to this embodiment, all n cutter motors 40 are configured to operate during ground excavation to rotate the cutter head 11. Furthermore, the tunnel boring machine 1 is also configured to operate only some (m) of the cutter motors 40 during ground excavation, depending on the excavation load, while keeping the remaining (nm) cutter motors 40 inactive to rotate the cutter head 11. Details of controlling the number of operating cutter heads 11 (m) according to the excavation load will be described later.

[0046] Furthermore, the hydraulic motor is an electric motor provided in the hydraulic unit that supplies hydraulic pressure to the hydraulic actuator. The hydraulic actuator is a variety of hydraulic actuators (for example, the shield jack 19, the actuator of the erector device, etc.) installed in the tunnel boring machine 1. The hydraulic unit is a device for supplying hydraulic pressure to the hydraulic actuator. This hydraulic unit includes, for example, a hydraulic pump that delivers oil to the hydraulic actuator and an electric motor (hydraulic motor) that generates the driving force to drive the hydraulic pump.

[0047] [2.2. Control System Configuration] Next, with reference to Figure 3, the control panel 100 and control device 110 provided in the tunnel boring machine 1 according to this embodiment will be described. Figure 3 is a schematic diagram showing the control panel 100 provided in the tunnel boring machine 1 according to this embodiment.

[0048] As shown in Figure 3, the control panel 100 is a device for controlling the tunnel boring machine 1. The control panel 100 includes a display unit 102, an operating unit 104, and a control device 110.

[0049] The display unit 102 is a display device that displays various information necessary for the operation of the tunnel boring machine 1. The display unit 102 is composed of, for example, a liquid crystal display device, a touch panel type liquid crystal display device, etc. The operation unit 104 is a device for workers to operate the tunnel boring machine 1 and input various information necessary for said operation (construction conditions, excavation conditions, etc.). Various input devices such as switches, levers, and touch panels can be used in this operation unit 104. If the display unit 102 is a touch panel type liquid crystal display device, the display unit 102 can also be used as the operation unit 104.

[0050] The control device 110 is a device for controlling various devices mounted on the tunnel boring machine 1. The control device 110 may control each part of the tunnel boring machine 1 based on operating instructions input by an operator to the operation unit 104, or it may automatically control each part of the tunnel boring machine 1 based on conditions set in advance by a program or the like.

[0051] The control device 110 can be configured as, for example, a PLC (Programmable Logic Controller). The control device 110 includes, for example, a processor, memory, an input interface, an output interface, a communication device, etc. (none of which are shown). The processor is composed of, for example, a CPU (Central Processing Unit) or other microprocessor. The processor executes a program stored in memory or other storage medium. This allows the control device 110 to perform various processes and realize various functions defined by the program.

[0052] Memory is a storage medium that stores programs and various other types of data. Examples of memory include RAM (Random Access Memory) and ROM (Read Only Memory). ROM is non-volatile memory that stores programs used by the processor and data necessary to run those programs. RAM is volatile memory that temporarily stores data such as variables, arithmetic parameters, and calculation results used in processes executed by the processor. Programs stored in ROM are read into RAM and executed by the processor, such as the CPU.

[0053] The control device 110 with the above configuration controls various devices such as electric motors mounted on the tunnel boring machine 1 according to a preset procedure. For example, during excavation of the ground by the tunnel boring machine 1, the control device 110 controls the number of operating cutter motors 40 m according to the excavation load acting on the cutter head 11. Details of this control of the number of operating motors m will be described later.

[0054] [2.3. Relationship between drilling load and power consumption] Here, with reference to Figure 4, the relationship between the excavation load of the tunnel boring machine 1 according to this embodiment and the power consumption (required power) of the cutter motor 40 will be explained in detail. Figure 4 is a schematic diagram showing the correlation between the excavation load and the power consumption of the cutter motor 40.

[0055] Excavation load is the load required to excavate the ground by the tunnel boring machine 1 (for example, the amount of mechanical or electrical energy consumed for excavation). Excavation load is a general term for the excavation resistance that fluctuates depending on various construction conditions and excavation conditions when the tunnel boring machine 1 excavates the ground.

[0056] As shown in Figure 4(a), the construction conditions during ground excavation by the tunnel boring machine 1 include, for example, the characteristics of the ground to be excavated (soil hardness, viscosity, overburden, groundwater level, etc.) and the degree of curvature of the excavation route. Specifically, the harder the soil, the greater the excavation load. Also, the higher the viscosity of the ground, the greater the excavation load. Also, the higher the overburden or groundwater level, the greater the excavation load. Also, the sharper the curve of the excavation route (the greater the curvature of the curve), the greater the excavation load.

[0057] Excavation conditions include, for example, the excavation speed (progression speed) when excavating the ground with the tunnel boring machine 1, and the degree to which excavated soil is taken in (removed). Specifically, the faster the excavation speed, the greater the excavation load. Also, the greater the amount of excavated soil taken in (removed), the smaller the excavation load.

[0058] As described above, the excavation load increases or decreases depending on the construction conditions and excavation conditions (see Figure 4(a)). In accordance with this increase or decrease in excavation load, the operating conditions of the cutter motor 40, which is the drive unit that rotates the cutter head 11 (see Figure 4(b)), change. The control device 110 controls and monitors the operating conditions of the cutter motor 40 in accordance with the excavation load when the tunnel boring machine 1 is excavating the ground.

[0059] As shown in Figure 4(b), the operating conditions of the cutter motors 40 include, for example, the number of cutter motors 40 in operation m, the rotational speed of the cutter motors 40, and the driving torque of each cutter motor 40. Of these, the rotational speed of each cutter motor 40 is correlated with the rotational speed of the cutter head 11, and the driving torque of each cutter motor 40 is correlated with the driving torque of the cutter head 11. The rotational speed and driving torque of the cutter motors 40 are converted into the current (load current) applied from the power supply 60 to each cutter motor 40.

[0060] As shown in Figure 4(c), the total power consumption of the cutter motors 40 is determined by the number of cutter motors 40 in operation m and the load current (Figure 4(b)). The total power consumption of the cutter motors 40 corresponds to the power consumption (required power) necessary to rotate the cutter head 11.

[0061] As described above, the excavation load increases or decreases depending on the various construction and excavation conditions of the tunnel boring machine 1 (Figure 4(a)). Furthermore, the various operating conditions of the cutter motor 40 change depending on the excavation load (Figure 4(b)). As a result, the total power consumption of the multiple cutter motors 40 increases or decreases depending on these operating conditions (Figure 4(c)).

[0062] [2.4. Control of the number of cutter motors 40 operating in accordance with the excavation load] Next, the operation control of the cutter motor 40 by the control device 110 according to this embodiment will be described.

[0063] As described above, the control device 110 controls the number of cutter motors 40 in operation m according to the excavation load while the tunnel boring machine 1 is excavating the ground. Specifically, the control device 110 automatically calculates the optimal number of cutter motors 40 in operation m according to the excavation load, operates only the cutter motors 40 corresponding to that optimal number of operation m, and stops the operation of the other cutter motors 40. Note that stopping the operation of a cutter motor 40 here does not mean that the physical rotation of the stopped cutter motor 40 stops, but rather that the stopped cutter motor 40 does not output rotational power itself, but is mechanically moved along with the rotating ring 14 which rotates due to the rotational power of the operating cutter motors 40. In this case, the stopped cutter motor 40 may be in a state where the power to the corresponding inverter 42 (see Figure 6) remains on, and operation has been stopped by a command from the inverter 42.

[0064] Furthermore, when reducing the number of operating cutter motors 40 as described above, the control device 110 reduces the number of operating cutter motors 40 as the excavation load decreases, thereby operating only a portion (m units) of the multiple (n units) cutter motors 40, and concentrating the load for generating rotational power for the cutter head 11 on these portion (m units) cutter motors 40.

[0065] This makes it possible to increase the load factor (motor output efficiency relative to supplied power) per cutter motor 40 operating during excavation by the tunnel boring machine 1. Therefore, while maintaining a high output efficiency for the operating cutter motors 40, excavation can be performed with high energy efficiency using the rotational power generated by the cutter motors 40. Thus, the total power consumption of the cutter motors 40 required for excavation can be suppressed, thereby saving energy.

[0066] For example, to handle hard ground (high excavation load), all of the numerous (n) cutter motors 40 mounted on the tunnel boring machine 1 can be operated continuously, thereby suppressing the waste of energy efficiency that occurs when excavating soft ground (low excavation load) with over-spec equipment. Also, when the excavation route extends from near the surface to great depths, multiple (n) high-spec cutter motors mounted to match the deep excavation (high excavation load) can be operated continuously, thereby suppressing the waste of energy efficiency that occurs when excavating near the surface (low excavation load) with over-spec equipment.

[0067] Thus, according to the optimization control of the number of operating cutter motors 40 according to this embodiment, in hard ground or deep excavation where the excavation load is high, even if all or many of the n cutter motors 40 are operated, the output efficiency (load factor) of each cutter motor 40 can maintain a high load of, for example, 30% or more, preferably 50% or more. On the other hand, in soft ground or shallow excavation where the excavation load is low, according to the excavation load, the number of operating cutter motors 40, m, is reduced and the operation of some cutter motors 40 is stopped. As a result, the output efficiency (load factor) per unit of the m operating cutter motors 40 can maintain a high load of, for example, 30% or more, preferably 50% or more. Therefore, regardless of whether the excavation load is high or low, the output efficiency of the m operating cutter motors 40 can be maintained at a high level. Thus, the cutter motors 40 can be operated with high energy efficiency and the power consumption of the entire cutter motors 40 can be suppressed, so that energy-saving construction by the tunnel boring machine 1 can be realized.

[0068] [2.5. Load factor R All [Control of the number of operating cutter motors 40 according to the load]] Next, a method for the control device 110 according to this embodiment to control the number of operating cutter motors 40 using the load factor R of the cutter motor 40 as the above excavation load will be described. All

[0069] As an index representing the above excavation load, for example, the load factor R of all (m units) of the cutter motors 40 during operation can be used. The load factor R of one cutter motor 40 during operation is represented by the following formula (1), and consider the case where the load factor R of all (m units) of the cutter motors 40 during operation All is represented by the following formula (2). All

[0070] R = P / Pk / 100 ···(1) R All = (P × m) / (Pk × n) / 100 ···(2) R: Load percentage of one cutter motor 40 [%] R All Load percentage of all 40 cutter motors [%] P: Power consumption per cutter motor 40 in operation [W] Pk: Rated output [W] of one cutter motor (40W) m: Number of cutter motors 40 in operation n: Total number of cutter motors (40)

[0071] In this case, the control device 110, while the tunnel boring machine 1 is excavating the ground, sets the load factor R as the excavation load. All The number of cutter motors 40 in operation m is controlled accordingly. For example, the load factor R representing the excavation load. All The higher the value, the more units are used, and the load factor R All The lower the load factor R, the fewer units are needed to operate. All The lower the value, the more preferable it is to reduce the number of operating units m, thereby operating only a portion (m units) of the n cutter motors 40 and stopping the operation of the remaining portion (nm units) of cutter motors 40, thereby concentrating the load for generating rotational power for the cutter head 11 on that portion (m units) of cutter motors 40.

[0072] This allows the overall load factor R of the cutter motor 40 when excavating the ground. All Accordingly, the number of cutter motors 40 in operation (m) can be optimized, and the load can be concentrated on m cutter motors 49. Therefore, the required number of cutter motors 40 can be driven for excavation while maintaining the output efficiency (motor output efficiency relative to supplied power) of each cutter motor 40 in operation. Thus, the total power consumption of the cutter motors 40 required for excavation can be suppressed, resulting in energy savings.

[0073] In addition, as mentioned above, the load ratio R of the entire cutter motor 40 in operation is used as an indicator of the excavation load. AllBy using this method, an index corresponding to the excavation load can be easily and appropriately detected and calculated. Therefore, the optimal number of cutter motors (m) to operate can be easily and appropriately controlled according to the excavation load.

[0074] The enlarged view in Figure 3 shows the excavation resistance (i.e., the overall load factor R of the cutter motor 40) during ground excavation by the tunnel boring machine 1. All An example is shown where image 106, which represents the fluctuation of ), is displayed on the display unit 102 of the control panel 100. If the excavation load fluctuates due to the various fluctuation factors mentioned above during excavation, the overall load ratio R of the cutter motor 40 will fluctuate accordingly. All However, it also fluctuates as shown in Figure 3. The control device 110 detects the power consumption of each cutter motor 40 and, in real time during excavation, the load factor R All Calculate the load factor R All The number of cutter motors 40 operating (m) is automatically increased or decreased in response to fluctuations in the system.

[0075] In this case, the control device 110 controls the load factor R which fluctuates over time. All The moving average value is calculated, and the load factor R All The number of cutter motors 40 in operation m may be increased or decreased based on the comparison result between the moving average value and a preset reference value. For example, the load factor R All A first reference value (e.g., 30%) and a second reference value (e.g., 50%) may be set as reference values. The control device 110 then calculates the load factor R during excavation. All When the moving average of falls below the second reference value (e.g., 50%), the number of operating units m is reduced to a predetermined second reference number m2 (e.g., if n=40 units, m2=32 units), and further, the load factor R All If the moving average of falls below the first reference value (for example, 30%), the number of operating units m may be reduced to a predetermined first reference number m1 (for example, if n=40 units, m1=20 units).

[0076] In this way, the control device 110 controls the load factor R AllBy automatically controlling the number of operating cutter motors 40 based on this, the number of operating motors can be automatically optimized according to the excavation load without the need for workers to manually control the number of operating motors during excavation. Therefore, overall power consumption of the cutter motors 40 can be reduced, and energy-saving construction by the tunnel boring machine 1 can be easily and in real time.

[0077] Furthermore, the worker can determine the load factor R by checking the image 106 on the display unit 102 of the control panel 100. All The fluctuations in the excavation resistance can be understood. Therefore, the worker can operate the control panel 100 to manually control the operation of the tunnel boring machine 1 according to the observed fluctuations in excavation resistance, and can manually adjust the number of cutter motors 40 in operation, their rotational speed, torque, and the excavation speed of the tunnel boring machine 1.

[0078] [2.6. High-load and low-load conditions of the cutter motor 40] As described above, the control device 110 optimizes the number of cutter motors 40 in operation m according to the excavation load, concentrating the load on some (m units) of cutter motors 40, thereby increasing the load ratio R per operating cutter motor 40 and improving the output efficiency of rotational power from each individual cutter motor 40. In other words, the control device increases or decreases the number of operating cutter motors 40 m according to the excavation load so that m units of cutter motors 40 in operation operate under high load conditions.

[0079] Here, we will explain the high-load state (appropriate high-efficiency state) and low-load state (inappropriate low-efficiency state) of the cutter motor 40, as well as the high-load region (appropriate high-efficiency region) and low-load region (inappropriate low-efficiency region) of the load factor R of the cutter motor 40.

[0080] In construction using tunnel boring machine 1, it is common practice to operate at a maximum of approximately 70% of the machine's capacity. When the excavation load is in the high-load range of 50-70% of the machine's capacity, the operator recognizes this as the optimal load from the perspective of the machine's output efficiency. Therefore, if the load factor R of the cutter motor 40 is between 50% and 70% of the cutter motor 40's rated output, the cutter motor 40 is operating under a high-load condition, meaning it is operating with high output efficiency of rotational power relative to the supplied power (an appropriate high-efficiency state).

[0081] On the other hand, if the excavation load is 30% or less of the tunnel boring machine 1's capacity, the contractor will clearly recognize that the work is being carried out under low load conditions. In this low-load condition of 30% or less, from the standpoint of electrical energy efficiency, the output efficiency of electric motors such as the cutter motor 40 is low, which is consistent with the contractor's recognition of low load. Therefore, if the load factor R of the cutter motor 40 is 30% or less of the cutter motor 40's rated output, it can be said that the cutter motor 40 is operating under low load conditions, with low output efficiency of rotational power relative to the supplied power (an inappropriately low-efficiency state).

[0082] Therefore, if the load factor R of each cutter motor 40 in operation is within the low-load range of the first reference value or less (for example, 30% or less), each cutter motor 40 will be operating in a low-load state with low output efficiency. As a result, the overall output efficiency of the cutter motors 40 relative to the supplied power decreases, which makes it difficult to achieve energy-saving construction.

[0083] Therefore, in order to avoid such problems, the control device 110 according to this embodiment ensures that the load ratio R of each cutter motor 40 in operation is outside the low load region of a first reference value (e.g., 30%) or less when excavating by the tunnel boring machine 1, and adjusts the overall load ratio R of the cutter motors 40 All The number of cutter motors 40 in operation m is controlled accordingly. This controls the load factor R AllAccordingly, the number of operating units (m) can be reduced to an appropriate number, allowing the load required for excavation to be concentrated on m cutter motors 40. Therefore, the load factor R of each of the m cutter motors 40 can be increased to the medium to high load range of the first reference value (e.g., 30%) or higher. Thus, it is possible to avoid the operation of the m cutter motors 40 in a low-load state (low-efficiency state), and the overall output efficiency of the cutter motors 40 can be improved. Consequently, the overall power consumption of the cutter motors 40 can be reduced, enabling energy-saving construction.

[0084] Furthermore, the control device 110 adjusts the overall load ratio R of the cutter motors 40 so that the load ratio R of each cutter motor 40 in operation is within the high load range of a second reference value (e.g., 50%) or higher, which is greater than the first reference value (e.g., 30%). All It is preferable to control the number of operating cutter motors 40 m accordingly. This allows for a load factor R All By optimizing the number of operating units (m) accordingly, the load required for excavation can be concentrated on the optimal number of operating cutter motors (m). Therefore, the load factor R of each of the m cutter motors 40 in operation can be kept within the high-load range (appropriate high-efficiency range) of a second standard value (e.g., 50%) or higher and a third standard value (e.g., 70%) or lower. Thus, since the m cutter motors 40 in operation can operate under high-load conditions (appropriate high-efficiency conditions), the overall output efficiency of the cutter motors 40 can be further improved. Consequently, the overall power consumption of the cutter motors 40 can be further reduced, enabling more energy-saving construction.

[0085] [2.7. Circuit Configuration and Operation of the Control System] Next, with reference to Figures 5 and 6, the circuit configuration of the control system for the tunnel boring machine 1 according to this embodiment and the control operation of the cutter motor 40 will be described. Figures 5 and 6 are schematic diagrams showing the circuit configuration of the control system for the tunnel boring machine 1 according to this embodiment. Figure 5 shows the circuit state during high-load operation of the tunnel boring machine 1. Figure 6 shows the circuit state during low-load operation of the tunnel boring machine 1.

[0086] As shown in Figures 5 and 6, the n cutter motors 40-1, 40-2, 40-3, ..., 40-n mounted on the excavator body 10 of the tunnel boring machine 1 are electrically connected to a power supply 60 for the tunnel boring machine 1. The power supply 60 is an AC power supply and is supplied to the power supply 60 from an external power supply facility (not shown) of the tunnel boring machine 1. Each cutter motor 40 is driven by the AC power supplied from the power supply 60.

[0087] Each cutter motor 40 and power supply 60 is connected to a power supply circuit which is provided with inverters 42-1, 42-2, 42-3, ... 42-n (hereinafter sometimes collectively referred to as "inverter 42") and switches 44-1, 44-2, 44-3, ... 44-n (hereinafter sometimes collectively referred to as "switch 44").

[0088] Each inverter 42 converts the AC power supplied from the power supply 60 into AC power of a predetermined frequency for the cutter motors 40 and supplies it to each cutter motor 40. The switch 44 connects / disconnects the circuit between each inverter 42 and the power supply 60, thereby supplying / stopping AC power to each inverter 42. When each switch 44 is turned on and AC power is supplied to each inverter 42, the AC power converted by each inverter 42 is supplied to each cutter motor 40, and the cutter motors 40 are driven. When each switch 44 is turned off and the power supply to each inverter 42 is cut off, the operation of the cutter motors 40 is also stopped.

[0089] The control device 110 is connected to each inverter 42 via a control line 112. The control device 110 transmits operation commands to each inverter 42 via the control line 112 and controls the operation of each inverter 42. Each inverter 42 transmits data representing the electrical load (energy) consumed by each inverter 42 to the control device 110 via the control line 112. This load data may include, for example, the current value of the power supplied to the cutter motor 40 through the inverter 42 and the torque value generated by the cutter motor 40. The control device 110 is also connected to each switch 44 via a control line 114. The control device 110 transmits on / off commands to each switch 44 via the control line 114 and controls the on / off state of each switch 44.

[0090] As shown in Figure 5, when the excavation load is relatively large and the tunnel boring machine 1 is operating under high load conditions, for example, all n cutter motors 40 are in operation, and the number of operating motors m = n. In this case, because the excavation load is large, the control device 110 turns on all n switches 44 and drives all n inverters 42 mounted on the tunnel boring machine 1. As a result, all n cutter motors 40 are in operation, and the load required to rotate the cutter head 11 is shared among the n cutter motors 40. In this case, as described above, each cutter motor 40 operates under high load conditions (that is, the load factor R of each cutter motor 40 is within the high load range of, for example, 50-70%), so the output efficiency of the rotational power from each cutter motor 40 is high. Therefore, the cutter motors 40 can be operated in a state of high energy efficiency relative to the supplied power.

[0091] In contrast, as shown in Figure 6, when the excavation load is relatively small and the tunnel boring machine 1 is operating under low load conditions, the control device 110 turns on only some switches 44-1, 44-3, ..., 44-n-1 and operates some inverters 42-1, 42-3, ..., 42-n-1, thereby operating only some (m units) of the n cutter motors 40, namely cutter motors 40-1, 40-3, ..., 40-n-1. Furthermore, the control device 110 turns off some switches 44-2, 44-4, ..., 44-n and stops some inverters 42-2, 42-4, ..., 42-n, thereby stopping the operation of the remaining nm units of cutter motors 40-2, 40-4, ..., 40-n.

[0092] As a result, the load is concentrated only on the m-unit cutter motors 40-1, 40-3, ..., 40-n-1, which are in operation. Therefore, these m-unit cutter motors 40-1, 40-3, ..., 40-n-1 operate in a high-load state (high-efficiency state) with high output efficiency relative to the supplied power, and the load factor R of these m-unit cutter motors 40 falls within the high-load region (high-efficiency region) of, for example, 50% or more. Thus, only the m-unit cutter motors 40 can be operated in a state of high energy efficiency relative to the supplied power. On the other hand, the n-unit cutter motors 40-2, 40-4, ..., 40-n, which are not in operation, do not consume power. Therefore, as shown in Figure 6, by operating only the m-unit cutter motors 40 when the excavation load is low, the total power consumption of the operating cutter motors 40 can be reduced compared to the case where all n-unit cutter motors 40 are operated in a low-load state (for example, load factor R of 30% or less) when the excavation load is low, thereby achieving energy-saving construction.

[0093] Furthermore, in the case shown in Figure 6, the control device 110 stops supplying power to inverters 42-2, 42-4, ..., 42-n connected to cutter motors 40-2, 40-4, ..., 40-n that are not being operated among the n cutter motors 40 by turning off switches 44-2, 44-4, ..., 44-n. This also reduces the internal power consumption of inverters 42-2, 42-4, ..., 42-n, thus further reducing the power consumption of the entire control system.

[0094] In other words, the power consumption of the cutter motor 40 is about the same as the power consumption of the inverter 42, but strictly speaking, it is less than the power consumption of the inverter 42 by the amount of the inverter 42's internal power consumption (for example, about 1kW). In other words, even when the cutter motor 40 is stopped, if power is still being supplied to the inverter 42 corresponding to the cutter motor 40 (the inverter 42 is powered on), the inverter 42 will consume internal power, and this internal power consumption will be wasted.

[0095] Therefore, as shown in Figure 6, by stopping the power supply to inverters 42-2, 42-4, ..., 42-n connected to cutter motors 40-2, 40-4, ..., 40-n that are not in operation (i.e., turning off the power to inverter 42), not only the power consumption of the cutter motors 40-2, 40-4, ..., 40-n but also the internal power consumption of the inverters 42-2, 42-4, ..., 42-n can be reduced, thereby further improving the energy-saving effect. In particular, the energy-saving effect by stopping the power supply to inverter 42 can be further improved when the capacity of inverter 42 is large or when there are many non-operating cutter motors 40. Thus, according to this embodiment, it is possible to further reduce the power consumption of the entire control system, including not only the power consumption of the cutter motors 40 but also the internal power consumption of inverter 42, and it is possible to measure the power consumption of the entire control system and evaluate the energy-saving effect.

[0096] [3. Detachable mechanism 50 for cutter motor 40] Next, the attachment / detachment mechanism 50 of the cutter motor 40 according to this embodiment will be described with reference to Figures 7 and 8. Figures 7 and 8 are a schematic diagram and a perspective view, respectively, showing the attachment / detachment mechanism 50 of the cutter motor 40 according to this embodiment.

[0097] As described above, in the tunnel boring machine 1 according to this embodiment, the excavation load (for example, load ratio R) All The number of cutter motors 40 in operation (m) is increased or decreased according to the load. For example, when the excavation load is low, only a portion (m units) of the n cutter motors 40 installed to handle high-load ground excavation are operated, and excavation is performed with the remaining cutter motors 40 stopped.

[0098] Here, all n cutter motors 40 are connected to the same power transmission mechanism 16. The power transmission mechanism 16 consists of a rotating ring 14, etc., as shown in Figure 1, and is a mechanism for mechanically transmitting the rotational power of the n cutter motors 40 to the cutter head 11. Therefore, the rotational power generated by the operating cutter motor 40 is mechanically transmitted to the non-operating cutter motor 40 via the rotating ring 14 of the power transmission mechanism 16. Consequently, the non-operating cutter motor 40 is mechanically dragged along with the rotation of the rotating ring 14, and this dragging of the non-operating cutter motor 40 generates mechanical resistance. As a result, the rotational power generated by the operating cutter motor 40 is not only consumed for the rotation of the cutter head 11, but is also wasted due to the dragging resistance of the non-operating cutter motor 40, resulting in mechanical power loss and energy loss. In particular, when excavating soft ground, if the excavation load remains low for a long distance, there is a problem in that energy loss due to the rotational resistance of the cutter motor 40 while it is not in operation increases.

[0099] To solve the problem of energy loss due to such rotational resistance, the tunnel boring machine 1 according to this embodiment is equipped with a cutter motor 40 detachment mechanism 50 in order to physically disconnect the cutter motor 40 from the power transmission mechanism 16 when it is not in operation.

[0100] The detachment mechanism 50 is a mechanism for attaching and detaching the cutter motor 40 to the power transmission mechanism 16 that transmits rotational power to the cutter head 11. The detachment mechanism 50 attaches the cutter motor 40 to be operated from among the n cutter motors 40 to the power transmission mechanism 16, and detaches the cutter motor 40 that is not being operated from the power transmission mechanism 16.

[0101] Here, "attachment" means mechanically connecting the output shaft of the cutter motor 40 to the power transmission mechanism 16, thereby enabling mechanical power transmission between the cutter motor 40 and the power transmission mechanism 16. On the other hand, "detachment" means mechanically disconnecting the output shaft of the cutter motor 40 from the power transmission mechanism 16, thereby preventing mechanical power transmission between the cutter motor 40 and the power transmission mechanism 16. For example, in the example of the connection structure between the cutter motor 40 and the power transmission mechanism 16 shown in Figure 1, if the drive gear 40a at the tip of the cutter motor 40 is engaged with the ring gear 14a of the rotating ring 14 of the power transmission mechanism 16, the cutter motor 40 is considered attached to the power transmission mechanism 16. On the other hand, if the drive gear 40a of the cutter motor 40 is not engaged with the ring gear 14a of the rotating ring 14 and is able to rotate freely, the cutter motor 40 is considered detached from the power transmission mechanism 16.

[0102] Here, with reference to Figures 7 and 8, a specific example of the configuration of the cutter motor 40 attachment / detachment mechanism 50 according to this embodiment will be described. Figures 7(a) and 8(a) show the state in which the cutter motor 40 is attached to the power transmission mechanism 16 by the attachment / detachment mechanism 50, and Figures 7(b) and 8(b) show the state in which the cutter motor 40 is pulled out from the power transmission mechanism 16 and detached by the attachment / detachment mechanism 50.

[0103] As shown in Figures 7 and 8, the attachment / detachment mechanism 50 of the cutter motor 40 according to this embodiment includes a movable cylinder 51, a slide jack 52, a support plate 53, a flange 54, a guide cylinder 55, a positioning pin 56, and a pin hole 57.

[0104] The movable cylinder 51 is, for example, a cylindrical member having a cylindrical shape. The movable cylinder 51 is arranged to surround the outer circumference of the cutter motor 40 and is fixed to the outer surface of the cutter motor 40.

[0105] The slide jack 52 is, for example, a hydraulic jack that generates power to move the cutter motor 40 in the forward and backward direction (axial direction). The slide jack 52 comprises a jack body 52a and a telescopic rod 52b. The base end (front end) of the jack body 52a is fixed to a support plate 53, and the support plate 53 is fixed to the excavator body 10. The telescopic rod 52b is provided so as to be able to extend and retract in the forward and backward direction relative to the jack body 52a by hydraulic power. The tip (rear end) of the telescopic rod 52b is fixed to the outer circumferential surface of the movable cylinder 51.

[0106] The front end of the movable cylinder 51 is provided with a ring-shaped flange 54 that protrudes outward. A pin hole 57 for inserting a positioning pin 56 is formed through the flange 54 in the front-to-back direction.

[0107] The guide tube 55 is positioned so that the front portion of the cutter motor 40 can be inserted through it, and is fixed to the excavator body 10. The inner diameter of the guide tube 55 is slightly larger than the outer diameter of the front portion of the cutter motor 40. The guide tube 55 is a member that guides the forward and backward movement of the cutter motor 40 when the cutter motor 40 moves (slides) in the forward and backward direction by the slide jack 52.

[0108] Furthermore, a positioning pin 56 is provided protruding rearward from the rear end surface of the guide cylinder 55. The positioning pin 56 is sized to pass through a pin hole 57 provided in the flange 54 and is positioned at a location corresponding to the pin hole 57. The positioning pin 56 and pin hole 57 have the function of positioning the cutter motor 40 to a predetermined position when the cutter motor 40 moves forward, and also have the function of receiving the rotational reaction force when the cutter motor 40 rotates. Only one set of positioning pins 56 and pin holes 57 may be provided, or multiple sets may be provided.

[0109] The detachment mechanism 50, configured as described above, allows for convenient attachment and detachment of the cutter motor 40 to and from the power transmission mechanism. Specifically, as shown in Figures 7(a) and 8(a), when the slide jack 52 of the detachment mechanism 50 is retracted, the cutter motor 40 moves forward together with the movable cylinder 51 and is mounted on the power transmission mechanism 16. In this mounted state, the drive gear 40a at the tip of the cutter motor 40 meshes with the ring gear 14a of the rotating ring 14 of the power transmission mechanism 16. Therefore, when the cutter motor 40 is operated, the rotational power generated by the cutter motor 40 is transmitted from the drive gear 40a to the ring gear 14a. In the mounted state shown in Figure 8(a), the positioning pin 56 is inserted into the pin hole 57, positioning the cutter motor 40 in the appropriate position, so that the drive gear 40a and the ring gear 14a mesh securely, and rotational power can be transmitted appropriately.

[0110] On the other hand, as shown in Figures 7(a) and 8(a), when the slide jack 52 is extended, the cutter motor 40 moves backward together with the movable cylinder 51, and the cutter motor 40 detaches from the power transmission mechanism 16. In this detached state, the drive gear 40a at the tip of the cutter motor 40 is disconnected from the ring gear 14a of the rotating ring 14. Therefore, in the detached state, the cutter motor 40 does not rotate along with the rotation of the rotating ring 14, and power is not mechanically transmitted from the rotating ring 14 to the cutter motor 40.

[0111] As described above, the detachment mechanism 50 according to this embodiment allows the cutter motor 40 to be operated to be securely attached to the power transmission mechanism 16, as shown in Figures 7(a) and 8(a). On the other hand, as shown in Figures 7(b) and 8(b), the cutter motor 40 that is not being operated can be detached from the power transmission mechanism 16. This allows the cutter motor 40 that is not in operation to be mechanically disconnected from the power transmission mechanism 16 during excavation, preventing it from rotating along with the rotating ring 14 of the power transmission mechanism 16, which is rotated by the rotational power of other operating cutter motors 40. Therefore, no mechanical energy loss occurs due to the resistance of the rotation of the cutter motor 40 that is not in operation. Thus, the overall power consumption of the cutter motor 40 can be further reduced, and more energy-saving construction can be achieved.

[0112] [4. Specific examples of operation control of the cutter motor 40] Next, a specific example of the operation control of the cutter motor 40 according to this embodiment will be described.

[0113] [4.1. Specific Example of Operation Control 1] First, with reference to Figure 9, a specific example of operating with a reduced number of cutter motors 40 (reduced operation) when the excavation load is low will be described. Figure 9 is a schematic diagram showing the operating state of multiple cutter motors 40 arranged circumferentially within the excavator body 10 of the tunnel boring machine 1 according to this embodiment. Figures 9(a) and (b) both show an example in which 15 cutter motors 40 are arranged circumferentially within the excavator body 10 (total number of cutter motors 40 n = 15).

[0114] The example in Figure 9(a) shows the case where the excavation load is relatively low (for example, the overall load ratio R of the cutter motor 40). AllHowever, in the case of a moderate load range of 30-50%, an example is shown where the number of operating cutter motors m is reduced to about half for reduced operation. Specifically, out of 15 cutter motors 40, 8 cutter motors 40-1, 40-3, 40-5, 40-7, 40-8, 40-10, 40-12, and 40-14 are in operation (number of operating units m = 8). On the other hand, 7 cutter motors 40-2, 40-4, 40-6, 40-9, 40-11, 40-13, and 40-15 are stopped.

[0115] As shown in Figure 9(a), eight cutter motors 40 that are in operation and seven cutter motors 40 that are not in operation are arranged alternately in the circumferential direction. This allows rotational power to be transmitted evenly and stably in the circumferential direction from the eight operating cutter motors 40, which are evenly distributed along the circumferential direction, to the rotating ring 14 of the power transmission mechanism 16.

[0116] Furthermore, in the example shown in Figure 9(a), when reducing the number of cutters in the medium load range, the non-operating cutter motors 40 are not detached from the power transmission mechanism 16 by the detachment mechanism 50, but are allowed to rotate together while remaining attached to the power transmission mechanism 16. In other words, the seven non-operating cutter motors 40 are mounted on a rotating ring 14 that rotates using the rotational power of the other eight operating cutter motors 40, and rotate together with the rotation of the rotating ring 14. Thus, during reduced operation, the seven non-operating cutter motors 40 may be allowed to rotate together without being detached from the power transmission mechanism 16. This allows for immediate activation of the non-operating cutter motors 40 to increase rotational power even if the excavation load suddenly increases during excavation, thus enabling accurate response to high-load excavation conditions.

[0117] The example in Figure 9(b) shows the case where the excavation load is quite low (for example, the overall load ratio R of the cutter motor 40). AllHowever, in the case of a low load area of ​​30% or less, an example is shown in which the number of operating cutter motors 40 m is reduced by about half, and all of the cutter motors 40 that are not in operation are disconnected from the power transmission mechanism 16 for reduced operation. Specifically, of the 15 cutter motors 40, eight cutter motors 40-4, 40-5, 40-6, 40-7, 40-8, 40-9, 40-10, and 40-11 located on the lower side of the excavator body 10 are in operation (number of operating motors m = 8). On the other hand, seven cutter motors 40-1, 40-2, 40-3, 40-12, 40-13, 40-14, and 40-15 located on the upper side of the excavator body 10 are not in operation.

[0118] As shown in Figure 9(b), when operating with reduced capacity in a low-load region, the seven cutter motors 40 that are not in operation are detached from the power transmission mechanism 16 by the detachment mechanism 50 to prevent them from rotating together. This prevents mechanical energy loss caused by the rotation of the seven cutter motors 40 that are not in operation, and thus further reduces the overall power consumption of the cutter motors 40.

[0119] Furthermore, in the example shown in Figure 9(b), approximately half of the cutter motors 40 located on the lower side of the excavator body 10 are operated, while approximately half of the cutter motors 40 located on the upper side are deactivated. By concentrating the operating cutter motors 40 on the lower side of the excavator body 10 in this way, rotational power can be concentrated and transmitted to the lower side where the load is high due to the effects of gravity, etc., so that rotational power can be efficiently transmitted from the cutter motors 40 to the rotating ring 14. This leads to the prevention of mechanical energy loss and has the effect of reducing the overall power consumption of the cutter motors 40.

[0120] [4.2. Specific Examples of Operation Control 2] Next, with reference to Figure 10, a specific example of the criteria for determining the number of cutter motors 40 in operation m according to the excavation load of the control device 110 of the tunnel boring machine 1 according to this embodiment will be described. Figure 10 is a table showing the criteria for determining the number of cutter motors 40 in operation m according to this embodiment. Figure 10 shows an example of determination when 40 cutter motors 40 are mounted on the boring machine body 10 (total number of cutter motors 40 n = 40).

[0121] As shown in Figure 10, the control device 110 controls the load ratio R, which is an index representing the excavation load. All Accordingly, the number of cutter motors 40 in operation m and whether or not it is necessary to detach the cutter motors 40 by the detachment mechanism 50 are determined in multiple stages. Here, the load factor R All If it is 30% or less, the excavation load is low, and the load factor R All If it is between 30% and 50%, the excavation load is a moderate load, and the load factor R All If the percentage is 50% or higher, the excavation load is high.

[0122] R All When the load is 50% or higher, the control device 110 operates all 40 cutter motors 40 (number of operating units m=n=40). In this case, even if all cutter motors 40 are operating, the load factor R of each individual cutter motor 40 will be 50% or higher, so each cutter motor 40 can operate in a high-load state with high output efficiency (appropriate high-efficiency state). Therefore, the overall output efficiency of the 40 cutter motors 40 can also be set to a high-load state of 50% or higher (appropriate high-efficiency state).

[0123] Also, R AllWhen the load is moderate, between 40% and 50%, the control device 110 operates 32 cutter motors 40 (m=32 units) and stops 8 cutter motors 40. Then, all 8 stopped cutter motors 40 are kept connected to the power transmission mechanism 16 without being detached. As a result, the load factor R of each operating cutter motor 40 becomes 50% to 62.5%, allowing them to operate in a high-load state (appropriate high-efficiency state) with high output efficiency.

[0124] Similarly, R All When the load is moderate, at 30-40%, the control device 110 operates 24 cutter motors 40 (m=24 units) and stops 16 cutter motors 40. Then, all 16 stopped cutter motors 40 are kept connected to the power transmission mechanism 16 without being detached. As a result, the load factor R of each operating cutter motor 40 becomes 50-66.7%, allowing them to operate in a high-load state (appropriate high-efficiency state) with high output efficiency.

[0125] Also, R All When the load is low, at 25-30%, the control device 110 operates 20 cutter motors 40 (m=20 units) and then stops all 20 cutter motors 40. The control device then keeps all 20 stopped cutter motors 40 connected to the power transmission mechanism 16 without detaching them. As a result, the load factor R of each operating cutter motor 40 becomes 50-60%, allowing them to operate in a high-load state (appropriate high-efficiency state) with high output efficiency.

[0126] Furthermore, R AllWhen the load is low, less than 25%, the control device 110 operates 20 cutter motors 40 (m=20 units) and stops operating 20 cutter motors 40. Then, all 20 stopped cutter motors 40 are detached from the power transmission mechanism 16 so that they do not move together. In this way, even when the load is low, less than 25%, half of the 20 cutter motors 40 are operated to prepare for unforeseen circumstances during excavation, but the 20 stopped cutter motors 40 are detached from the power transmission mechanism 16 to suppress power loss caused by the movement of the 20 stopped cutter motors 40. This suppresses mechanical energy loss and the resulting waste of power consumption caused by the movement of the 20 stopped cutter motors 40, and if an unforeseen situation occurs during excavation (for example, if the excavation load suddenly increases), the output of the 20 operating cutter motors 40 can be increased to respond quickly.

[0127] Note that in the example shown in Figure 10, R All In the case where the load is less than 25%, all 20 cutter motors 40 that are not in operation are detached from the power transmission mechanism 16, but the present invention is not limited to this example. For example, some of the cutter motors 40 that are not in operation may be operated in conjunction with the power transmission mechanism 16 while remaining attached.

[0128] More specifically, of the 20 cutter motors 40 that are not in operation (hereinafter referred to as "non-operating cutter motors 40"), only some (for example, 10) of the non-operating cutter motors 40 may be detached from the power transmission mechanism 16, while the other some (for example, 10) of the non-operating cutter motors 40 remain attached to the power transmission mechanism 16 and rotate together. By detaching some of the non-operating cutter motors 40 from the power transmission mechanism 16, mechanical power loss caused by the rotation of those non-operating cutter motors 40 can be suppressed. On the other hand, by keeping the other some non-operating cutter motors 40 attached to the power transmission mechanism 16, in the event of unforeseen circumstances (for example, if the ground suddenly hardens and the output of the operating cutter motors 40 becomes insufficient), the other some non-operating cutter motors 40 that remain attached can be temporarily and urgently activated to immediately increase the rotational power of the entire cutter motor 40, allowing high-load excavation to continue.

[0129] Furthermore, in situations where the excavation load is low, some (for example, 20) of the non-operating cutter motors 40 may be detached from the power transmission mechanism 16, and some (for example, 5) of the remaining 20 cutter motors 40 may be stopped to create a running state, while only some (for example, 15) of the cutter motors 40 are operated. This makes it possible to further increase the output efficiency of some (for example, 15) of the operating cutter motors 40. Moreover, if the output of some (for example, 15) of the operating cutter motors 40 becomes insufficient, the rotational power of the entire cutter motor 40 can be immediately increased by restarting some (for example, 5) of the stopped non-operating cutter motors 40.

[0130] Preferred embodiments of the present invention have been described above with reference to the attached drawings, but it goes without saying that the present invention is not limited to these embodiments. It will be obvious to those skilled in the art that various modifications or alterations can be conceived within the scope of the claims, and these will naturally also fall within the technical scope of the present invention.

[0131] For example, in the above embodiment, an example of a tunnel boring machine 1 of the earth pressure type (including the mud pressure type) was described, but the tunnel boring machine according to the present invention may also be a slurry type tunnel boring machine.

[0132] Furthermore, although the components of the tunnel boring machine 1 have been described in the above embodiment with reference to the drawings, the dimensions and positional relationships of the components in the drawings are merely illustrative, and the dimensions and positional relationships of the components of the tunnel boring machine 1 are not limited to the examples shown in the drawings. In addition, components may be added, deleted, or modified as appropriate for the tunnel boring machine 1 illustrated in the drawings. [Explanation of Symbols]

[0133] 1. Tunnel boring machine 2. Excavation face 10 Excavator body 11 Cutter head 12 Bulkhead 13 Cutter rotation shaft 14 Rotating Rings 14a Ring Gear 15 Linked beams 16 Power transmission mechanism 17 Chambers 19 Shield Jack 20 Screw conveyors 40 Cutter motor 40a drive gear 50 Detachable mechanism 51 Movable tube 52. Slide Jack 53 Support plate 54 Flange 55 Guide tube 56 Positioning pins 57 Pin holes 60 power supply 110 Control device S segment T Tunnel

Claims

1. The excavator body and A cutter head is rotatably mounted at the front end of the excavator body, Multiple cutter motors that generate rotational power for the cutter head, A control device that controls the number of cutter motors to be operated from among the multiple cutter motors, according to the excavation load when the cutter head excavates the ground, Equipped with, The control device reduces the number of operating units as the excavation load decreases, thereby operating only some of the multiple cutter motors and concentrating the load for generating the rotational power on those some cutter motors, in a tunnel boring machine.

2. The load factor R of one cutter motor in operation is expressed by the following formula (1), and the load factor R of all cutter motors in operation Ａｌｌ However, in the case represented by the following formula (2), The control device is During the excavation of the ground by the tunnel boring machine, the excavation load is the load ratio R Ａｌｌ The tunnel boring machine according to claim 1, which controls the number of operating units m accordingly. R=P / Pk / 100...(1) R Ａｌｌ =(P×m) / (Pk×n) / 100 ・・・(2) R: Load percentage of one cutter motor [%] R Ａｌｌ : Load percentage of all cutter motors [%] P: Power consumption per cutter motor in operation [W] Pk: Rated output [W] of one cutter motor m: Number of cutter motors in operation n: Total number of cutter motors

3. The control device is The load factor R of each cutter motor in operation is set to be outside the low load region, which is below the first reference value. Ａｌｌ The tunnel boring machine according to claim 2, wherein the number of operating units m is controlled accordingly.

4. The control device is The load factor R of each cutter motor in operation is set to fall within the high load region, which is greater than the second reference value and greater than the first reference value. Ａｌｌ The tunnel boring machine according to claim 3, wherein the number of operating units m is controlled accordingly.

5. The system further includes multiple inverters that convert power from a power source and supply it to each of the cutter motors, The tunnel boring machine according to claim 1, wherein the control device stops supplying power to the inverter connected to the cutter motor that is not being operated among the plurality of cutter motors.

6. A power transmission mechanism that connects the cutter head and the plurality of cutter motors, and transmits the rotational power generated by at least some of the plurality of cutter motors to the cutter head, A detachment mechanism for attaching and detaching each of the cutter motors to the power transmission mechanism, Furthermore, The aforementioned attachment / detachment mechanism is The cutter motor to be operated from among the multiple cutter motors is mounted on the power transmission mechanism. The tunnel boring machine according to any one of claims 1 to 5, wherein at least some of the cutter motors that are not in operation among the plurality of cutter motors are detached from the power transmission mechanism.

7. The aforementioned attachment / detachment mechanism is Some of the cutter motors that are not in operation are detached from the power transmission mechanism. The tunnel boring machine according to claim 6, wherein some of the cutter motors that are not in operation remain attached to the power transmission mechanism.

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