JP3797793B2 - Shield machine and shield method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a shield machine and a shield method that can cut an anchor that appears in front of a cutter head.
[0002]
[Prior art]
Around urban areas, anchors for supporting earth retaining walls and water blocking walls are still buried in the ground. This anchor is formed of a stranded wire of a PC steel wire and has a high strength and cannot be easily cut. If such an anchor appears forward while digging with a shield machine, it may become an obstacle to digging and make it impossible to dig. However, until now, since a highly practical anchor cutting means that can be operated in the machine of a shield machine has not been developed, when conducting excavation of an underground mine with a shield machine, a preliminary survey was conducted prior to the excavation. However, when an anchor appears on the excavation route, the anchor is pulled out in advance.
[0003]
[Problems to be solved by the invention]
However, even if such a survey is conducted, if a large number of anchors are driven in the vicinity of the shield machine's drilling path, the anchor driving angle is not within the plan. The anchor may not have been pulled out in advance, so an unexpected anchor may be encountered when drilling with a shield machine. In such a case, the anchor cannot be found in advance before the excavation of the natural ground where the anchor is located, and since the anchor cannot be found immediately after the excavation, the excavation is continued as it is at the previous excavation speed. A cutter bit for excavating natural ground bites into the anchor. And since the cutter bit for excavating natural ground has a wide blade width and poor cutting performance, the cutting resistance of the cutter bit suddenly increases and the cutter torque rises rapidly. As a result, the cutter head is caught by the anchor. May become impossible to drive.
In such a case, after the periphery of the face was hardened by an auxiliary method such as chemical injection, an operator had to enter the face and cut it with a gas cutter to remove it. Such a construction method requires a lot of time and labor since a person needs to go out and work, and there are many problems in terms of safety.
[0004]
The present invention is intended to solve such problems found in the prior art, and the technical problem is to provide a shield machine and shield method that can cut the anchor by its rotation without the cutter head being caught by the anchor. It is to provide.
[0005]
[Means for Solving the Problems]
These technical problems of the present invention are:
In a shield machine, a main cutter bit for excavating natural ground is attached to the cutter head and excavating the natural ground with the cutter head while propelling with a shield jack,
“At least PC steel wire can be cut and the blade width 10mm or less, manufactured to a predetermined value considering hardness and toughness A plurality of cutting bits that have a cutting edge and can rotate while revolving when attached to the cutter head are attached at least on the same peripheral surface of the outer periphery of the cutter head, leading the outer peripheral side of the excavation cross section. This is achieved by the technical means of the first invention of this application, which is arranged so that it can be cut in such a manner that the anchor appearing in front of the cutter head can be cut with a cutting bit.
In the shield method,
" A plurality of leading bits for cutting the cutting face prior to the main cutter bit are configured so that at least the PC steel wire can be cut and the blade width is about 1/3 or less of the main cutter bit. Attached to the cutter head so that the inner peripheral side of the excavated cross section can be cut, and these bits are arranged so that the cutting bit can cut the outer peripheral side of the excavated cross section in advance. The first step of excavating the ground using a shield machine and detecting the presence of an anchor located in the excavation path during the excavation, and after detecting the presence of the anchor by this first step, The propulsion speed is reduced to at least a speed at which the cutter head cannot be driven, and the second step of excavating the face is used to cut the anchor with the preceding bit. "Technique of the second invention of this application It is also achieved by means.
[0006]
In the first invention of this application, since the cutting bit is attached to the outer periphery of the cutter head, when the anchor is cut with the cutting bit, the anchor appears at any position in the shield path of the shield machine. Even so, the cutting bit can be applied to the anchor to cut it. In addition, since the cutting bit is arranged so that the outer peripheral side of the excavation cross section can be cut in advance, this cutting bit can be first applied to the anchor. The cutting bit is configured to be able to rotate while revolving, and in addition to reducing the cutting resistance by itself, the cutting width of the cutting edge can be reduced. 10mm or less, set to a predetermined value considering hardness and toughness Normal roller bit than By narrowing, when cutting the anchor, even if the biting amount is increased, the cutting resistance can be relatively lowered, and the cutting resistance can be suppressed very low for the biting amount. The driving torque of the cutter head does not increase extremely. Therefore, even if the shield machine encounters the anchor and continues to dig as it is, a situation in which the cutter head is caught by the anchor and cannot be driven does not easily occur. Therefore, even if necessary measures such as reducing the propulsion speed after sensing this after encountering the anchor, there will be no serious situation that the cutter head can not be driven. The anchor can be cut. In addition, a plurality of anchors are mounted on the same peripheral surface of the cutter head, and the alternative anchors are crushed during one rotation of the cutter head. Even if the value is set low, it is possible to prevent the anchor cutting speed from decreasing.
[0007]
When the present invention is embodied, if the technical means according to claim 2 of the claims is adopted, the leading bit for cutting the face prior to the main cutter bit is set to approximately 1/3 or less of the main cutter bit. Since it is configured to be narrow and attached to the cutter head so that the inner circumference side can be cut from the cutting bit, even if the anchor hits the preceding bit on the inner circumference side of the cutting bit, the normal main cutter Since it hits a preceding bit with a narrow blade width different from that of the bit, cutting resistance can be reduced when the anchor is cut with the preceding bit. When the technical means described in claim 2 of this claim is adopted and embodied, in particular, if the technical means described in claim 3 of this claim is adopted, a plurality of pieces attached in the radial direction are provided. The leading bits are arranged so that the tip of the cutting edge becomes lower toward the outer peripheral side, and the anchor hardly hits multiple leading bits at the same time, so when cutting the anchor with the leading bit, the cutter head The driving torque can be concentrated on one leading bit having a narrow blade width, the anchor can be cut effectively, and the cutting resistance can be greatly reduced.
[0008]
When the present invention is embodied, if the technical means described in claim 4 of the claims is adopted, the cutting bit is provided with a plurality of notches at intervals so that corners are formed on the outer periphery. Since the anchor is provided so as not to move at the notch, the anchor can be cut by being caught at the corner portion, and the anchor can be cut more effectively.
When the present invention is embodied, if the technical means described in claim 5 of the claims is adopted, the shield machine has an anchor detection device for detecting an anchor located in the excavation path. Since the presence of an anchor located in the excavation path can be detected in advance, the excavation speed can be reduced and adjusted to an optimum value for cutting the anchor prior to the cutting of the anchor. The drilling of the face can be continued as it is.
When the present invention is embodied, if the technical means according to claim 6 of the claims is adopted, the ground is gripped by the rolling prevention device and the reaction force of the driving torque of the cutter head is taken by the ground. Therefore, even when the driving torque of the cutter head temporarily increases for some reason, the shield body can be prevented from rolling by the reaction force.
[0009]
When the present invention is embodied, if the technical means described in claim 7 of the claims is adopted, even if the cut anchor is entangled with the screw conveyor, the inspection port is opened and the anchor is removed. There is no fear that the screw conveyor will be unable to drive. In the case where the technical means described in claim 7 of this patent claim is adopted and embodied, in particular, if the technical means described in claim 8 of this claim is adopted, such an inspection port is provided in the screw conveyor. In addition, the screw conveyor is removably attached to the partition wall, and a blocking gate is provided to open and close the partition wall opening provided at the tip of the screw conveyor. By retracting the conveyor and shielding the opening with a blocking gate, it can be safely removed in a state where the removal operation is easy.
[0010]
In the second invention of this application, when an anchor appears in the excavation path of the shield machine in the construction process by the shield method, the presence of the anchor is detected in advance, and after the detection, the propulsion of the shield machine is performed. Since the speed is reduced to at least the speed so that the cutter head can not be driven and the face is dug, even if the anchor is cut with the preceding bit by the rotation of the cutter head when the shield machine is dug, The cutter head is not caught by the anchor and cannot be driven.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the invention related to the shield machine of this application showing how the present invention is actually embodied will be described with reference to FIGS. 1 to 5, and the shield machine of this application and The embodiment of each invention related to the shield method will be clarified. 1 is a side sectional view of a shield machine according to an embodiment of the present invention, FIG. 2 is a view taken in the direction of arrow A-A in FIG. 1, and FIG. 3 is a shield machine according to an embodiment of the present invention. 4 is an enlarged cross-sectional view of the cutting bit in FIG. 4, FIG. 4 is an arrow cross-sectional view of FIG. 3, and FIG. 5 is an enlarged cross-sectional view of the main part of a normal roller bit for comparison with the cutting bit of FIG. is there.
[0012]
1 to 4, 1 has a cutter head 2 at the front, a cylindrical shield body driven by a shield jack 1a, and 2 includes a spoke 3 and an outer ring 4 to which various cutter bits are attached. The head 3 is a spoke radially provided on the rotating shaft 3 a of the cutter head 2, and 4 is an outer ring that is attached to the spoke 3 so as to surround the spoke 3 and defines the outer periphery of the cutter head 2. The cutter head 2 is constituted by the spoke 3 and the outer peripheral ring 4 in this embodiment, but may be constituted by a face plate. 5 is a center bit for digging the center of the face, 6 is a ground radar for detecting the anchor 21, 7 is described in detail later, a cutting bit which is a cutter bit dedicated to cutting the anchor 21, and 8 is described in detail later. A leading bit for cutting the cutting face prior to the main cutter bit 9, a main cutter bit 9 for excavating a natural ground, 10 for a copy cutter for excavation, and 11 for driving the copy cutter 10 A rotary joint for connecting the pressure oil pipe and additive injection pipe to the rotary shaft 3a side, 12 a slip ring for connecting the wiring of the underground radar 6 to the rotary shaft 3a side, and 13 a cutter head drive This is an electric motor with a reduction gear. Note that the slip ring 12 incorporates a rotary encoder for detecting the rotational position of the cutter head 2.
[0013]
The center bit 5 serves to reduce excavation resistance by centering the face. The center bit 5 is formed in a convex shape by attaching a number of preceding bits 8 to a chevron-shaped attachment member with a protruding tip, and is provided concentrically with the rotary shaft 3 a at the center of the cutter head 2. A number of such leading bits 8 are attached not only to the center portion of the cutter head 2 but also to each of the cutter porks 3 and are characteristic of this embodiment. The specific technical contents will be described in detail later. To do. The underground radar 6 is provided near the outer periphery of the cutter head 2 and functions to detect the anchor 21 located in the excavation path by rotationally driving the cutter head 2. The technical significance of providing the underground radar 6 as the anchor detection device in the shield machine is directly related to the technical content of the second invention relating to the shield method of this application. The effect will be described in detail. The cutting bit 7 is configured to rotate while revolving when attached to the cutter head 2, and functions to cut the anchor 21 that appears in front of the cutter head 2. Since the cutting bit 7 is the greatest feature of this embodiment, specific technical contents will be described in detail in the next stage. A large number of main cutter bits 9 for excavating natural ground are attached to the front surface of each spoke 3 and the outer peripheral ring 4 forming a vertical plane at a predetermined interval, and those attached to the spoke 3 are as shown in FIG. The height is changed so that the tip located on the outer peripheral side is lower. Whatever type of shield machine is used, only the main cutter bit 9 is attached to the cutter head 2 as an indispensable bit, and the ground is excavated by the cutter head 2 while propelled by the shield jack 1a. Excavate in the ground.
[0014]
Next, the technical contents of the cutting bit 7 which is the most characteristic feature of this embodiment will be described in detail with reference to FIGS. As shown in FIG. 3, the cutting bit 7 is inserted into a ring-shaped cutter portion 7d having a cutting edge 7a on the outer peripheral portion and a central insertion hole of the cutter portion 7d, and is inserted through a roller bearing 7f and a ball bearing 7g. It is comprised with the fixed axis | shaft part 7e which supports the cutter part 7d rotatably. A plurality of cutting bits 7 having such a structure are attached on the same peripheral surface of the outer peripheral portion of the cutter head 2. That is, in this embodiment, as shown in FIG. 2, about four cutting bits 7 are attached to the outer ring 4 at regular intervals via brackets, and the tips of the cutting edges 7a of the cutting bits 7 are on the same circumference. To be located. Accordingly, when the cutter head 2 is rotated by driving the motor 13 with a reduction gear, the cutting bit 7 revolves with the rotation of the cutter head 2, while the cutter portion 7d rotates about the fixed shaft portion 7e. When the anchor 21 is cut, it rolls while pressing the linear anchor 21, so it is cut and cut as if it is crushed. Since the cutting bit 7 is configured as described above, its structure is similar to a so-called roller bit, but the specific structure of the cutter portion 7d is different.
[0015]
Therefore, the specific structure of the cutter part 7d of the cutting bit 7 will be described in detail. The cutter part 7d has a blade width W of the blade edge 7a, as is clear when FIG. 3 is compared with FIG. ₂ Is the blade width W of a normal roller bit ₁ The blade width W ₂ Is formed so as to be significantly narrower than the ordinary roller bit of FIG. The blade width means the width of the root of the chevron at the cutting edge of the bit, as is apparent from FIGS. 3 and 5. Such blade width W ₂ When the anchor 21 is cut using a narrow cutting bit 7, the cutting resistance can be greatly reduced as long as the biting amount of the cutting edge 7a is the same as compared with the case of cutting with a normal roller bit. Therefore, even when an unexpected anchor is encountered when digging with a shield machine, the cutter torque rapidly rises and the cutter head 2 is caught by the anchor 21 and stops. Does not occur easily. Cutting width 7 of cutting bit 7 ₂ Specifically, the blade width W ₂ Is preferably selected in the range of 6 mm or more and 10 mm or less in consideration of the size of the cutter torque of the shield machine and the propulsion distance. However, the blade width W of the cutting bit 7 ₂ However, if it is in the range of 10 mm or less, the lower limit value takes into consideration the material such as hardness and toughness of the cutting edge 7a. However, the design may be selected as appropriate. By the way, the blade width W of a normal roller bit ₁ Is generally in the range of 16 mm to 20 mm and the cutting width W of the cutting bit 7 ₂ There is a considerable gap.
[0016]
The anchor 21 is generally made of a PC steel wire, and since there are few things that are harder to cut than the PC steel wire, the cutting edge 7a of the cutting bit 7 is made of a cemented carbide tip or a special steel for induction hardening, What is necessary is just to be manufactured with the material of the performance which PC steel wire can cut at least. The cutting bit 7 precedes the outer peripheral side of the excavation cross section so that the tip of the cutting edge 7a is positioned ahead of the leading edge of the leading bit 8 or the main cutter bit 9 cutting the adjacent area of the cutting locus. And arranged so that it can be cut. In this embodiment, a large number of notches 7b are formed on the circumference of the cutting edge 7a of the cutting bit 7 at intervals. Unlike the normal roller bit, the cutting bit 7 is formed with such a notch 7b. Therefore, the cutting bit 7 is formed with the notch 7b while restraining the strand of the anchor 21 from moving with the notch 7b. It can cut | disconnect so that it may be hooked on the corner | angular part 7c. As a result, the strands of the anchor 21 can be cut not only by the cutting edge 7a but also intermittently hooked on the corner portion 7c, so that the anchor 21 can be cut very efficiently.
[0017]
The technical content of the preceding bit 8 that characterizes this embodiment will be described in detail. The leading bits 8 are not only provided at the center of the cutter head 2 as described above, but also a large number are attached to the center of each cutter pork 3 at intervals. This type of leading bit can be attached to a normal shield machine as needed, but its purpose is to cut the face prior to the main cutter bit 9 to cut the face into a ring at predetermined intervals. This is to make it easy to collapse, and to reduce the area of the main cutter bit 9 hitting the natural ground so that the natural ground can be easily excavated. The preceding bit 8 in this embodiment not only fulfills such a function, but also functions to cut the anchor 21 without hitting the main cutter 9 even if the anchor 21 appears on the inner peripheral side of the cutter head 2. However, in order to be able to demonstrate these functions, the following unique measures are taken.
[0018]
That is, the leading bit 8 is made of a material capable of cutting at least a PC steel wire, like the cutting bit 7, and the cutting width can be configured to be narrower than that of the main cutter bit 9 to reduce cutting resistance. I have to. The blade width of the leading bit 8 is formed to be approximately 1/3 or less of the blade width of the normal main cutter bit 9, but considering the magnitude of the cutter torque of the shield machine, etc., 10 mm to 30 mm It is desirable to select within the range. However, the width of the blade is better as it is narrowed in terms of reducing the cutting resistance by removing the strength and durability, so if it is in the range of 30 mm or less, the lower limit value is such as the hardness and toughness of the blade edge. What is necessary is just to select suitably on design, considering a material etc. A plurality of such leading bits 8 are attached to the cutter head 2 so that the inner peripheral side of the excavation cross section can be cut more than the cutting bit 7. In this embodiment, the plurality of leading bits 8 are aligned and mounted at the center of the spoke 3 so that the leading bits 8 are mounted in the radial direction of the cutter head 2, and the tips of the leading edges of the leading bits 8 are shown in FIG. As shown, it is arranged so as to become lower toward the outer peripheral side. When the cutting bit 7, the preceding bit 8, and the main cutter bit 9 described above are arranged, the line connecting the leading edge of the leading bit 8 to the main cutter bit 9 is l. ₁ The cutting bit 7 is advanced so that it comes forward only, and the cutting edge 7 is l from the line connecting the leading edge of the leading bit 8 to the cutting edge. ₂ The cutting bit 7 is arranged so as to be able to cut the outer peripheral side of the excavation cross-section ahead of the preceding bit 8 so as to come forward only.
[0019]
The shield machine according to this embodiment is capable of cutting the anchor 21 in front of the cutter head 2 with the structure as described above. This point will be described. 14 is a shut-off gate jack that is installed on the partition wall 1b of the shield machine and drives the shut-off gate 15. 15 is a shut-off gate that is slidably attached to the partition wall 1b and opens and closes the opening 16 by the shut-off gate jack 14. 16 is the partition wall 1b. An opening provided at the tip of the screw conveyor 17 in the above, 17 is advanced to a position corresponding to the opening 16 of the partition wall 1b, a screw conveyor that is removably attached and discharges excavated earth and sand, 18 advances the screw conveyor 17, A slide jack 19 that is driven to move backward is an inspection port provided near the tip of the screw conveyor 17. In the shield machine, when the anchor 21 is cut by the cutter head 2, the cut anchor 21 may be entangled near the entrance of the screw conveyor 17. The inspection port 19 is provided to open and remove the anchor 21 when the cut anchor 21 is entangled near the entrance of the screw conveyor 17. When the anchor 21 is removed from the inspection port 19 in this way, the screw conveyor 17 is driven by the slide jack 18 so that _Four Then, the blocking gate 15 is driven by the blocking gate jack 14, and the opening 16 is blocked by the blocking gate 15.
[0020]
20 is an anti-rolling device as a gripper for preventing the shield body 1 from rolling when the anchor 21 is cut, 21 is an anchor formed of a stranded wire of PC steel wire, and 22 is a support for the anchor 21. Mortar for use. The anti-rolling device 20 has a gripper member that can be projected and retracted in the radial direction of the shield body and that can be caused to bite into the ground when projecting, and this gripper member is caused to appear and disappear by a suitable driving means such as a jack Be able to. A plurality of such anti-rolling devices 20 are provided on the front body side of the shield body 1. In the shield machine, when the anchor 21 is cut by the cutter head 2, the driving torque 2 of the cutter head 2 generated by the cutting resistance temporarily rises, and the shield body 1 may roll. For example, when the cutter head 2 is started after restarting the cutting of the anchor 21 with the cutter head 2 or when the cutting resistance suddenly increases when the anchor 21 is cut, the cutter torque may temporarily increase. is there. When the reaction force at the time of cutting the anchor 21 is large as described above, the anti-rolling device 20 removes the gripper member from the outer periphery of the shield body 1. _Three The shield body 1 is gripped and gripped, and the reaction force of the driving torque 2 of the cutter head 2 generated by cutting resistance is taken by the ground mountain, thereby preventing the shield body 1 from rolling.
[0021]
The operation and effect of this embodiment will be described. Since the shield excavator of this embodiment is provided with the underground radar 6 as an anchor detection device, when encountering the anchor 21 during excavation, the presence of the anchor 21 located in the excavation path is detected as a first step. Detect in advance. After detecting the presence of the anchor 21 in this way, as a second step, the operator reduces the propulsion speed of the shield machine to an optimum speed for cutting (cutting) the anchor 21 with the cutting bit 7 or the leading bit 8. In this way, the driving speed of the shield jack 1a is adjusted and the face is excavated as it is. Most preferably, the propulsion speed of the shield machine is adjusted so that the amount of biting into the anchor 21 of the cutting bit 7 is 1 mm or more and 2 mm or less per minute. Thus, the anchor 21 is cut by the cutting bit 7 by continuing the excavation of the natural ground while adjusting the propulsion speed with the shield excavator. The detection capability of the underground radar 6 is about 60 cm at present, but it is sufficiently possible to detect this before the bit provided on the cutter head hits the anchor 21. In order to cut the anchor 21, it is necessary to apply a reaction force to the supporting mortar 22 enclosing the anchor 21, but when the surrounding ground is soft and the reaction force cannot be expected, the propulsion speed of the shield machine It is necessary to reduce the amount of biting of the cutting bit 7 into the anchor 21 by further reducing the reaction force and to reduce the reaction force generated when the anchor 21 is cut.
[0022]
When cutting the anchor 21 with the cutting bit 7 in this way, the cutting bit 7 is attached to the outer periphery of the cutter head 2, so that the anchor 21 appears at any position in the excavation path of the shield machine. The cutting bit 7 can be applied to the anchor 21 and cut. In addition, the cutting bit 7 is less than the preceding bit 8 by 1 ₁ The cutting bit 7 which is most suitable for cutting the anchor 21 in each bit of the cutter head 2 is firstly attached to the anchor 21 because it is arranged so that the outer peripheral side of the excavation surface can be advanced in advance. You can guess. Since the cutting bit 7 can rotate while revolving as the cutter head 2 rotates, the cutting resistance itself can reduce the cutting resistance. In addition, unlike a normal roller bit, the blade width is extremely narrow, 10 mm or less, and substantially less than half of the roller bit. Therefore, when the anchor 21 is cut, the cutting resistance is relatively increased even if the biting amount is increased. The cutting resistance can be kept very low for the amount of biting. In the shield machine of the present specific example, the drive torque of the cutter head 2 does not increase extremely even if the propulsion speed is not reduced by devising these ideas for the cutting bit 7. Therefore, even if the digging is continued without reducing the propulsion speed after encountering the anchor, a situation in which the cutter head 2 is caught by the anchor 21 and cannot be driven does not easily occur. Therefore, after encountering the anchor 21, even if necessary measures such as reducing the propulsion speed after detecting this at the time of cutting, a serious situation may occur in which the cutter head 2 cannot be driven. In addition, the anchor 21 can be cut by the rotation without the cutter head 2 being caught by the anchor 21.
[0023]
Further, four cutting bits 7 are attached on the same circumferential surface of the cutter head 2, and the four alternative anchors 21 are crushed during one rotation of the cutter head 2. Even when the amount of biting is set as low as 1 mm or more and 2 mm or less per minute, the propulsion speed of the shield machine is not reduced so much. Further, in this embodiment, the cutting bit 7 is provided with a notch 7b so that the corner 7c is formed on the cutting edge 7a, unlike a normal roller bit. While being restrained so as not to move, the anchor 21 can be cut so as to be hooked on the corner portion 7c, and the anchor 21 can be cut very efficiently.
[0024]
In the shield machine of this embodiment, when the anchor 21 is encountered during excavation, the anchor 21 is normally cut by cutting with the cutting bit 7 as described above, but the anchor 21 is the center of the cutter head 2. In the case of a shield machine that does not have the preceding bit 8 when it appears close, the anchor 21 may simultaneously hit a plurality of main cutter bits 9 and the cutting efficiency of the anchor 21 may be reduced. For this reason, in this embodiment, the leading bit 8 having a narrow blade width of 30 mm or less and approximately half or less of the main cutter bit 9 is cut so that the face can be cut prior to the main cutter bit 9. A plurality of heads 2 are attached. Therefore, even if the anchor 21 hits the leading bit 8 on the inner peripheral side of the cutting bit 7, it hits the leading bit 8 with a narrow blade width, and the cutting resistance when the anchor 21 is cut with the leading bit 8. Can be reduced, and the cutting efficiency of the anchor 21 does not decrease. In addition, since a plurality of the preceding bits 8 are attached in the radial direction of the cutter head 2 and the plurality of the preceding bits 8 are positioned on the outer peripheral side, the tip of the blade edge is arranged to be lower. Hardly hits multiple preceding bits 8 at the same time. Therefore, this not only reduces the cutting resistance at the time of cutting the anchor 21 with the leading bit 8, but also concentrates the driving torque 2 of the cutter head 2 on the single leading bit 8 having a narrow blade width. Thus, the anchor 21 can be effectively cut and cut.
[0025]
In particular, the shield machine according to this embodiment has an underground radar 6 for detecting the anchor 21 located in the excavation path, and can detect the presence of the anchor 21 located in the excavation path in advance. When the anchor 21 is cut by the technical means as described above, the excavation speed can be reduced and adjusted to an optimum value for cutting the anchor 21 prior to the cutting, and the cutting work of the anchor 21 can be efficiently performed. While doing so, the drilling of the face can continue without interruption. In the case where the shield method is carried out in the ground where the anchor 21 is embedded in the excavation route of the shield machine, the presence of the anchor 21 located in the excavation route is detected in advance, and after the presence of the anchor 21 is detected. If the propulsion speed of the shield machine is adjusted and at least reduced to a speed at which the cutter head 2 cannot be driven, the face is excavated, and the anchor 21 is cut by the preceding bit 8 by such a process. Even if the cutter bit 2 of the shield machine is not equipped with an optimum cutter bit for cutting the anchor 21 such as the cutting bit 7, if the leading bit 8 capable of cutting at least the PC steel wire is attached, the cutter The head 2 can be cut by the rotation without being caught by the anchor 21. The purpose of the period is achieved. The second invention of the present application relates to a process for implementing such a shield method.
[0026]
In the shield machine of this embodiment, since the rolling prevention device 20 is provided in particular, the cutter head 2 is restarted when the anchor 21 is cut by projecting the gripper member and gripping the ground. Even if the driving torque of the cutter head 2 temporarily increases for some reason, the shield body 1 can be prevented from rolling by the reaction force. Since the shield machine of this embodiment is an earth pressure shield machine equipped with the screw conveyor 17, the cut anchor 21 becomes entangled with the tip of the screw conveyor 17, and the screw conveyor 17 cannot be driven. There are also concerns. However, in this embodiment, the screw conveyor 17 is attached to the partition wall 1b so that the screw conveyor 17 can be moved forward and backward, and can be moved backward by the slide jack 18, and the opening 16 of the partition wall 1b provided at the tip position of the screw conveyor 17 is Even if the cut anchor 21 is entangled with the screw conveyor 17 in order to provide an inspection port 19 that can be opened and closed as necessary so that the shut-off gate 15 can be driven by the shut-off jack 14, it can be screwed. By retracting the conveyor 17 and shielding the opening 16 with the blocking gate 15, the anchor 21 entangled with the screw conveyor 17 can be safely removed from the inspection port 19 in a state where the removal work is easy.
[0027]
In this embodiment, the cutting bit 7 is provided with a large number of notches 7a, but these notches 7a are additional technical means for enabling the anchor cutting operation to be performed more effectively. These can be omitted as necessary.
[0028]
【The invention's effect】
As is clear from the above description, the first invention related to the shield machine of this application employs the technical means described in claim 1 of the claims, and therefore, the shield machine of the present invention is used. Accordingly, the anchor can be cut by the rotation without the cutter head being caught by the anchor. Also, since the alternative anchor can be crushed during one rotation of the cutter head, the cutting speed of the anchor is reduced even if the amount of biting into the anchor is set low. Can be prevented.
[0029]
When embodying the first invention of this application, in particular, if the technical means described in claim 2 of the claims is adopted, the anchor should hit the preceding bit on the inner peripheral side of the cutting bit. Even in this case, the anchor can be cut by this leading bit without reducing the cutting efficiency. When the technical means described in claim 2 of this patent claim is adopted and embodied, in particular, if the technical means described in claim 3 of this claim is adopted, the anchor is cut by the preceding bit in this way. In this case, the driving torque of the cutter head can be concentrated on one preceding bit having a narrow blade width, and the anchor can be cut effectively. When the first invention of this application is embodied, particularly when the technical means described in claim 4 of the claims is adopted, when the anchor is cut by the cutting bit, the anchor is cut by the cutting bit. While being restrained so as not to move, the anchor can be cut by being caught at the corner formed by the notch, so that the anchor can be cut more effectively. When embodying the first invention of this application, in particular, if the technical means according to claim 5 of the claims is adopted, the presence of the anchor located in the excavation path is detected in advance. Prior to this cutting, the excavation speed can be reduced and adjusted to an optimum value for the cutting, and the excavation of the face can be continued as it is while the anchor cutting operation is efficiently performed.
[0030]
When the first invention of this application is embodied, in particular, if the technical means described in claim 6 is employed, even if the driving torque of the cutter head temporarily increases, the reaction force This prevents the shield body from rolling. When embodying the first invention of this application, in particular, if the technical means described in claim 7 of the claims is adopted, even if the cut anchor is entangled with the screw conveyor, the inspection port can be opened. The anchor can be removed by opening, and there is no fear that the screw conveyor cannot be driven. When the technical means described in claim 7 of this patent claim is adopted and embodied, in particular, if the technical means described in claim 8 of this patent claim is adopted, the inspection port is thus opened and cut. When removing the anchor, it can be safely removed in a state where it can be easily removed.
[0031]
Since the second invention related to the shield method of this application employs the technical means described in claim 9 of the claims, the first invention related to the shield machine of this application is also based on the invention of this shield method. As in the second aspect, the cutter head can be cut by its rotation without being caught by the anchor.
[Brief description of the drawings]
FIG. 1 is a side sectional view of a shield machine according to an embodiment of the present invention.
FIG. 2 is a view taken in the direction of arrow AA in FIG.
FIG. 3 is an enlarged sectional view of a cutting bit in a shield machine according to an embodiment of the present invention.
4 is a view taken in the direction of arrows BB in FIG. 3;
FIG. 5 is an enlarged cross-sectional view of a main part of a normal roller bit for comparison with the cutting bit of FIG. 3;
[Explanation of symbols]
1 Shield body
1a Shield Jack
2 Cutter head
3 spokes
4 outer ring
5 Center bit
6 Ground penetrating radar
7 Cutting bit
7a cutting edge
7b Notch
7c Corner
7d fixed shaft
7e Fixed shaft
8 Leading bit
9 Main cutter bit
14 Blocking gate jack
15 Shutdown gate
16 opening
17 Screw conveyor
18 Slide jack
19 Inspection port
20 Rolling prevention device
21 Anchor

Claims (9)

The main cutter bit for excavating natural ground is attached to the cutter head, and it is possible to cut at least PC steel wire and cut the blade width in a shield excavator that excavates the natural ground with the cutter head while propelling it with a shield jack. A cutting bit that is 10 mm or less and has a cutting edge manufactured to a predetermined value in consideration of hardness and toughness, and is configured to rotate while revolving when attached to the cutter head, at least the outer periphery of the cutter head A plurality of parts are mounted on the same peripheral surface of the section, arranged so that the outer peripheral side of the excavation cross section can be cut in advance, and the anchor appearing in front of the cutter head can be cut with a cutting bit. Shield machine.   A plurality of leading bits for cutting the cutting face prior to the main cutter bit are configured so that at least the PC steel wire can be cut and the blade width is about 1/3 or less of the main cutter bit. The cutting head is attached to a cutter head so that the inner peripheral side of the excavation cross section can be cut, and these bits are arranged so that the cutting bit can cut the outer peripheral side of the excavation cross section in advance. Shield machine.   When attaching a plurality of leading bits to the cutter head, attach a plurality of leading bits in the radial direction of the cutter head, and attach the plurality of leading bits attached in the radial direction so that the tip of the cutting edge faces the outer peripheral side. 3. The shield machine according to claim 2, wherein the shield machine is arranged to be lowered.   4. The shield machine according to claim 1, wherein the cutting bit is provided with a plurality of notches at intervals so that corners are formed on the outer periphery.   The shield excavator according to claim 1, 2, 3, or 4, further comprising an anchor detection device for detecting an anchor located on the excavation path.   A rolling prevention device is provided for preventing rolling by gripping the ground and taking the reaction force of the driving torque of the cutter head on the ground. The shield machine according to claim 4 or 5.   A screw conveyor is provided as means for discharging excavated earth and sand, and the screw conveyor is provided with an inspection port for opening and removing the cut anchor when it is entangled near the entrance. The shield machine according to claim 2, claim 3, claim 4, claim 5 or claim 6.   8. The shield machine according to claim 7, wherein the screw conveyor is removably attached to the partition wall, and a blocking gate is provided to open and close the partition wall opening provided at the tip of the screw conveyor. A first step of excavating the ground using the shield machine according to claim 2 and detecting the presence of an anchor located in the excavation path during the excavation, and the presence of the anchor was detected by the first step. After that, the anchor bit is cut by the preceding bit by lowering the propulsion speed of the shield machine to at least a speed at which the cutter head cannot be driven and excavating the face. Shield construction method.

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