JP2016056570A - Tunnel excavation device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device for excavating the foundation by rotating a cutter head while pressing the cutter head against the foundation, which can prevent the damage of the cutter head at a low cost.SOLUTION: A columnar or cylindrical tunnel excavation device for excavating a tunnel on the foundation comprises a cutter part 30 at the tip which excavates the foundation by rotating around a center shaft of the tunnel excavation device. The cutter part 30 comprises a roller bit 38 and a drilling bit 40 installed in a planar tip surface part 20A, and a protrusive rib 39 which is installed so as to protrude from the tip surface part 20A and which holds sediment so that the sediment produced by scraping of the foundation by the roller bit 38 and the drilling bit 40 can cover the tip surface part 20A when the cutter part 30 rotates.SELECTED DRAWING: Figure 6

Description

  The present invention relates to a tunnel excavating apparatus for excavating a tunnel in the ground.

  In recent years, as a method of excavating a tunnel in the ground, a step of excavating the ground at a position corresponding to the outer ring portion of the tunnel in an annular shape with a cylindrical excavator, and a ground remaining in a columnar shape inside the excavator A method of constructing a tunnel by performing a process of excavating a pit is proposed.

  The present applicants have an annular cutter head having a plurality of excavation bits attached to the front of the excavator for excavating a tunnel by such a method, and the cutter head is rotated while being pressed against the ground. Therefore, an apparatus for excavating the ground in an annular shape has been proposed (see Patent Document 1).

JP 2014-5679 A

  Here, in the excavator as described above, the cutter head is rotated at a speed of about 3 rotations per minute while being constantly pressed against the ground. For this reason, especially when excavating hard ground such as rock, the cutter head may be worn by friction with the ground, especially hard rock or rock, and a hole may be formed. As described above, when a hole is formed in the cutter head, the strength required for the excavation work cannot be maintained. Therefore, it is necessary to repair the cutter head by stopping the excavation work, resulting in a delay in the excavation work.

  In order to prevent such a breakage of the cutter head, it is conceivable to increase the thickness of the steel plate constituting the cutter head, or to change the material of the cutter head to one having high friction resistance. However, these methods have a problem that the manufacturing cost of the cutter head becomes high.

  The present invention has been made in view of the above problems, and an object thereof is to prevent damage to the cutter head at a low cost in an apparatus for excavating the ground by rotating the cutter head while pressing the cutter head against the ground.

  The excavator of the present invention is a columnar or cylindrical tunnel excavator for excavating a tunnel in the ground, and a cutter head that excavates the ground by rotating around the central axis of the tunnel excavator is provided at the tip. The cutter head is provided so as to protrude from the tip surface and the excavation bit provided on the flat tip surface, and when the cutter head rotates, the earth and sand generated by the excavation bit shaving the ground remove the tip surface. And a projecting portion for holding earth and sand so as to cover.

  According to the present invention having the above-described configuration, since the tip surface of the cutter head is planar, and the earth and sand covers the tip surface by the projecting portion provided on the tip surface of the cutter head, the bedrock and rock directly touch the tip of the cutter head. Colliding with the surface can be prevented, thereby preventing the cutter head from being damaged. In addition, since the present invention only needs to provide a protruding portion, the cost can be reduced.

  In the present invention, preferably, the projecting portion is composed of a projecting rib provided to extend in the radial direction.

  According to the present invention having such a configuration, the protruding ribs are provided so as to extend in the radial direction, that is, so as to cross the rotation direction of the cutter head. Can be held.

In the present invention, preferably, the tunnel excavator is cylindrical, and the cutter head is annular.
In the present invention, preferably, the height of the protruding rib from the front end surface is lower than the height from the front end surface of the excavation bit.

  According to the present invention, damage to the cutter head can be prevented at a low cost in an apparatus for excavating the ground by rotating the cutter head while pressing it against the ground.

1 is a perspective view showing an excavator according to an embodiment of the present invention. It is a longitudinal direction vertical sectional view of the excavator shown in FIG. It is III-III sectional drawing in FIG. It is a front view of the excavator shown in FIG. It is VV sectional drawing in FIG. It is an expansion perspective view of the cutter part of the excavator shown in FIG. It is VII-VII sectional drawing in FIG. It is VIII-VIII sectional drawing in FIG. It is IX-IX sectional drawing in FIG. It is VV sectional drawing in FIG. 4 at the time of ground excavation. It is the schematic for demonstrating the method to convey excavation soil in the excavation apparatus shown in FIG.

  Hereinafter, an embodiment of a tunnel excavation apparatus and a tunnel excavation method of the present invention will be described in detail with reference to the drawings.

  1 to 9 show a drilling device 10 of the present embodiment, FIG. 1 is a perspective view, FIG. 2 is a longitudinal vertical sectional view, FIG. 3 is a III-III sectional view in FIG. 7, and FIG. 5 is a cross-sectional view taken along the line V-V in FIG. 4, FIG. 6 is an enlarged perspective view of the cutter unit, FIG. 7 is a cross-sectional view taken along the line VII-VII in FIG. 2 is a cross-sectional view taken along line IX-IX in FIG.

  As shown in FIGS. 1 and 2, the excavator 10 excavates the ground with a cylindrical shell 12, a drilling mechanism 14 provided at the tip of the shell 12 in the direction of excavation (hereinafter referred to as the front), and the ground. The excavation soil carry-out mechanism 16 for carrying out the excavated soil generated in this manner and the propulsion mechanism 18 for propelling the excavation mechanism 14 are provided.

  The shell 12 is composed of a rotating part shell 20, a first fixed part shell 22, a second fixed part shell 24, and a third fixed part shell 26 that are sequentially connected from the front. The

  The rotating portion shell 20 includes an annular tip surface portion 20A that forms a tip surface, a cylindrical outer cylinder 20B that extends rearward from the outer periphery of the tip surface portion 20A, and a cylinder that extends rearward from the inner periphery of the tip surface portion 20A. A cylindrical inner cylinder 20C.

  Further, the first fixed part shell 22, the second fixed part shell 24, and the third fixed part shell 26 have substantially the same diameter as the outer cylindrical body 20B of the rotating part shell 20, respectively. The formed cylindrical outer cylinders 22B, 24B, 26B and the outer cylinders 22B, 24B, 26B are arranged in substantially the same diameter as the inner cylinder 20C of the first fixed portion shell 22. The cylindrical inner cylinders 22C, 24C, 26C, and a plurality of support members (not shown) provided to connect the inner cylinders 22C, 24C, 26C and the outer cylinders 22B, 24B, 26B. The These shells 20, 22, 24, and 26 are each made of steel. The first fixed portion is formed such that a gap 20D is formed between the rear end of the inner cylindrical body 20C of the rotating portion shell 20 and the front end of the inner cylindrical body 22C of the first fixed portion shell 22. The shell 22 terminates in front of the front end of the inner cylindrical body 22C.

  Inner cylinders 20C, 22C, 24C, 26C and outer cylinders constituting the rotary part shell 20, the first fixed part shell 22, the second fixed part shell 24, and the third fixed part shell 26 The bodies 20B, 22B, 24B, and 26B are arranged concentrically and coaxially with the rotation shaft of the excavation mechanism 14 described in detail later, whereby the inner cylinders 20C, 22C, 24C, and 26C and the outer cylinders 20B, 22B, An annular space is formed between 24B and 26B. The support member is made of a rod-like or plate-like steel material, the number capable of supporting earth pressure acting on the outer cylinders 20B, 22B, 24B, 26B, with the central axis of the inner cylinders 20C, 22C, 24C, 26C as the center The inner cylinders 20C, 22C, 24C, and 26C and the outer cylinders 20B, 22B, 24B, and 26B are provided so as to radiate at appropriate intervals in the circumferential direction and the axial direction. The propulsion mechanism 18 is accommodated in an annular space between the inner cylinders 20C, 22C, 24C, and 26C and the outer cylinders 20B, 22B, 24B, and 26B.

  The rotating part shell 20 is rotatably connected to the first fixed part shell 22. Note that slipping can be improved by interposing a bearing or the like between the rotating portion shell 20 and the first fixed portion shell 22.

  Further, the front end portions of the inner cylindrical body 24C and the outer cylindrical body 24B of the second fixed portion shell body 24 are located between the inner cylindrical body 22C of the first fixed portion shell body 22 and the rear end portion of the outer cylindrical body 22B. It is housed in the space. With this configuration, the second fixed portion shell 24 is connected to the first fixed portion shell 22 so as to be slidable in the axial direction.

  Similarly, the front end portions of the inner cylinder body 26C and the outer cylinder body 26B of the third fixed portion shell body 26 are the rear end portions of the inner cylinder body 26C and the outer cylinder body 26B of the second fixed portion shell body 24, respectively. Is housed between. With this configuration, the third fixed portion shell 26 is connected to the second fixed portion shell 24 so as to be slidable in the axial direction. The connecting portion between the first fixed portion shell 22 and the second fixed portion shell 24 and the connecting portion between the second fixed portion shell 24 and the third fixed portion shell 26 are axially connected. A guide member for guiding the sliding may be provided.

  As shown in FIG. 2, the excavation mechanism 14 includes a cutter unit (cutter head) 30 including a plurality of excavation bits formed on the front end surface portion 20 </ b> A of the rotating unit shell 20, and a first fixed unit shell 22. And a reduction gear 32 and a motor 34 arranged.

  As shown in FIGS. 2 and 4, a plurality of openings 36 are formed in the distal end surface portion 20 </ b> A of the rotating portion shell 20 at intervals in the circumferential direction, and the space 20 </ b> E inside the rotating portion shell 20 is formed outside. Are communicated with each other through the opening 36.

  As shown in FIG. 4, the cutter unit 30 includes a plurality of roller bits 38 provided on the planar tip surface portion 20A of the rotating shell 20 at intervals in the circumferential direction, and openings formed in the tip surface portion 20A. A plate-shaped drilling bit 40 provided at the edge of 36, and a projecting rib 39 attached to the front end surface portion 20A of the rotating portion shell 20.

  The projecting rib 39 is made of, for example, a square bar made of steel such as SS400 (old JIS standard SS41). As shown in FIGS. 4 to 6, the projecting rib 39 extends from the inner edge to the outer edge in a substantially radial direction on the distal end surface portion 20 </ b> A of the rotating portion shell 20, and further, the front portion on the side surface of the rotating portion shell 20 is pivoted. It is provided to extend in the direction. Then, as will be described in detail later, the protruding rib 39 holds the earth and sand generated by excavation in a state in which the surface of the front end surface portion 20A of the rotating portion shell 20 is covered.

  In the present embodiment, the protruding rib 39 is a square bar having a width of 30 mm and a height of 30 mm, and the tip surface portion 20A of the rotating portion shell 20 is set so that the interval between the protruding ribs 39 adjacent in the circumferential direction is about 200 mm. Is attached. Further, these protruding ribs 39 are attached so as to cross the rotational direction (circumferential direction) of the rotating part shell 20. In order to hold earth and sand in a state of covering the surface of the tip end surface portion 20A of the rotating portion shell 20, the angle of the protruding rib 39 with respect to the radial direction is preferably 30 ° or less. That is, the angle of the protruding rib 39 with respect to the rotation direction (circumferential direction) is preferably 60 ° to 120 °. In the present embodiment, some protruding ribs 39 extend in a direction perpendicular to the rotation direction of the roller bit 38, and the other protruding ribs 39 extend in parallel with the drill bit 40.

  Note that the height of the protruding rib 39 from the tip surface portion 20A is lower than the height of the roller bit 38 and lower than the height of the drill bit 40. This is because, when the height of the protruding rib 39 from the tip surface portion 20A is higher than that of the roller bit 38 and the drilling bit 40, the protruding rib 39 hits the ground to be excavated, and the ground is caused by these bits. Because it is not possible to excavate. In general, since the height of the roller bit 38 and the drill bit 40 is about 50 mm, the height of the protruding rib 39 needs to be 50 mm or less. Further, the height of the projecting rib 39 is 10 mm or more so that the surface of the distal end surface portion 20A of the rotating portion shell 20 holds earth and sand having a thickness sufficient to protect the rotating portion shell 20. Is preferred.

  As shown in FIG. 2, a pin rack 35 is attached to the rear end portion of the rotary shell 20 via a ring 33. A reduction gear 32 is connected to the motor 34 disposed in the first fixed portion shell 22, and a pinion 37 is attached to the reduction gear 32. A pinion 37 attached to the speed reducer 32 meshes with a pin rack 35 attached to the rotating part shell 20. As a result, when the motor 34 rotates, the torque is amplified through the speed reducer 32 and transmitted to the rotating part shell 20, and the rotating part shell 20 is centered on the central axis. Rotates relative to the fixed shells 22, 24, 26.

  Each roller bit 38 is disposed at a different position in the radial direction. Thereby, when the rotary shell 20 rotates in the circumferential direction, the trajectory through which each roller bit 38 passes becomes a concentric circle having substantially equal intervals in the radial direction, and uniform excavation can be performed regardless of the diameter.

  Further, the drill bit 40 is formed of a bit having a sharp tip, and is excavated so that the cutting surface cut by the roller bit 38 is flattened by the rotation of the rotating shell 20.

  As shown in FIG. 9, the excavated soil carry-out mechanism 16 is provided in the space 20E inside the rotating part shell 20 so as to divide the space 20E in the rotating part shell 20 into a plurality of chambers 20F in the circumferential direction. The plurality of plate members 42 and the first fixing portion shell 22 are fixed to the front end portion of the inner cylindrical body 22C and attached so as to extend toward the rear end of the inner cylindrical body 20C of the rotating portion shell body 20. A closing plate 44 and a jet nozzle (not shown) provided on the surface of the front end face portion 20A of the rotary shell 20 so as to inject water toward the ground.

  Each plate member 42 is connected to the back surface of the tip surface portion 20A of the rotating portion shell 20 where the drill bit 40 is attached, and is provided perpendicular to the tip surface portion 20A. In the present embodiment, the plate member 42 is provided perpendicular to the distal end surface portion 20A. However, the present invention is not limited to this, and the plate member 42 is provided so as to be inclined in the circumferential direction of the rotary shell 20 toward the rear. Also good. Thus, by providing the plate member 42 in the rotating part shell 20, the rigidity of the rotating part shell 20 can be improved.

  The closing plate 44 has a predetermined clearance 20D between the rear end of the inner cylinder 20C of the rotating part shell 20 and the front end of the inner cylinder 22C of the first fixed part shell 22 from the lowermost part in the circumferential direction. Are provided so as to close the portion up to the height (in this embodiment, portions of about 120 ° on both sides in the circumferential direction from the lowermost portion).

  As shown in FIGS. 2, 3, 7, and 8, the propulsion mechanism 18 includes a front axial jack 52, a rear axial jack 50, a front radial jack 54, and a rear radial jack. 56 and an auxiliary propulsion jack 57.

  The front axial jack 52 is accommodated between the inner cylinders 22C and 24C and the outer cylinders 22B and 24B from the first fixed part shell 22 to the second fixed part shell 24, Is fixed to the support member of the first fixed part shell 22, and the rear end is fixed to the support member of the second fixed part shell 24.

  The rear axial jack 52 is accommodated between the inner cylinders 24C and 26C and the outer cylinders 24B and 26B from the second fixed part shell 24 to the third fixed part shell 26, Is fixed to the support member of the second fixed portion shell 24, and the rear end is fixed to the support member of the third fixed portion shell 26.

  A plurality of the front axial jacks 52 and the rear axial jacks 50 are provided at appropriate intervals in the circumferential direction so as not to interfere with other members.

  The front radial jack 54 is accommodated in the first fixed shell 22. The outer cylindrical body 22B of the first fixed portion shell 22 has an opening formed at a position corresponding to the front radial jack 54, and the front radial jack 54 extends radially outward from the excavator 10 through this opening. It can be expanded and contracted so as to protrude toward the direction.

  The rear radial jack 56 is accommodated in the third fixed shell 26. The outer cylinder body 26B of the third fixed portion shell body 26 is formed with an opening at a position corresponding to the rear radial jack 56, and the rear radial jack 56 passes through the opening from the radial outer side of the excavator 10. It can be expanded and contracted so as to protrude toward the direction.

The propulsion jack 57 is disposed below the rear end portion of the excavator 10 and can extend and contract toward the rear of the excavator 10.
The front axial jack 52, the rear axial jack 50, the front radial jack 54, the rear radial jack 56, and the propulsion jack 57 are connected to a control device (not shown). The hydraulic pressure is supplied by the control device.
A gantry 70 is held horizontally at the rear of the inner space of the excavator 10.

  As shown in FIG. 2, the excavation system 1 includes an excavated soil receiving plate 100, a sieving mechanism 102, a hopper 104, a rock crusher 106, and a conveyor 81 as the excavated soil carry-out mechanism 16.

  The excavated soil receiving plate 100 is a plate material that extends horizontally from the inner side of the rotating portion shell 20 toward the rear. The excavated earth receiving plate 100 is provided at a height equal to the lower end of the inner surface of the inner cylindrical body 20C of the rotating part shell 20, and the inner cylindrical body 20C of the rotating part shell 20 and the first fixed part shell 22 is provided. , 22C so that no gap is generated between them.

  The sieving mechanism 102 extends horizontally rearward from the rear end of the excavated soil receiving plate 100. The sieving mechanism 102 is made of steel plates arranged in a lattice or parallel at predetermined intervals. Rocks and earth and sand of a predetermined size (for example, about 25 cm or less) fall downward, and rocks of a larger size are It is a member that does not fall. The front end of the sieving mechanism 102 extends in the horizontal direction continuously to the rear end of the excavated soil receiving plate 100. The excavated earth receiving plate 100 and the sieving mechanism 102 are provided at a lower height than the gantry 70.

  The front end of the conveyor 81 is located below the sieving mechanism 102 and extends rearward. The lower part of the inner cylinders 22C, 24C, and 26C of the first fixed part shell 22, the second fixed part shell 24, and the third fixed part shell 26 is cut over a predetermined width, A conveyor 81 is disposed in the cut portion. The conveyor 81 extends rearward, is inclined obliquely upward at the rear portion of the excavator 10, and the rear end is located above the rear conveyor 81. The inner space of the excavator in the present invention is not limited to the inner side of the inner cylinders 22C, 24C, 26C. As described above, the space includes the space in which the inner cylindrical bodies 22C, 24C, and 26C are cut and open toward the center of the apparatus.

  The hopper 104 is located directly below the sieving mechanism 102 and above the conveyor 81, and has a shape such that the cross-sectional area narrows downward. The excavated soil that has fallen through the sieving mechanism 102 is guided by the hopper 104 so as to fall on the conveyor 81.

  The crusher 106 is a two-shaft type crusher having a screw-shaped crushing bit. As such a crusher, for example, a sizer manufactured by MMD can be used. The crusher 106 is arranged directly above the conveyor 81 so that the upper end of the front part is connected to the rear end of the sieving mechanism 102 and the rear end is located below the gantry 70. Further, the crusher 106 is provided with an inclination of, for example, about 10 degrees so that the rear side is positioned higher than the front side.

Hereinafter, a method for constructing a tunnel by the tunnel excavation system of this embodiment will be described.
In the present embodiment, the tunnel having a circular cross section is constructed by excavating the ground in an annular cross section with the excavator 10 and excavating the remaining ground in the center with the breaker 62 later.

Hereinafter, a method for excavating the ground in an annular cross-section by the excavator 10 will be described.
When excavating the ground, while the excavator 10 is propelled by the propulsion mechanism 18, the rotating part shell 20 is rotated with respect to the fixed part shells 22, 24, and 26, and further, the excavating soil carrying mechanism 16 excavates. This is done while discharging the soil.

  In order to propel the excavator 10, first, the rear radial jack 56 is extended radially outward to press the surrounding ground. Then, the rear axial jack 50 is extended in a state where a reaction force is applied to the surrounding ground by the rear radial jack 56. Thereby, the rotating part shell 20, the first fixed part shell 22, and the second fixed part shell 24 are pushed forward with respect to the third fixed part shell 26. At this time, the ground can be excavated in an annular shape by the roller bit 38 and the drill bit 40 by rotating the rotary shell 20.

  That is, the motor 34 of the excavation mechanism 14 is rotated in a state where the cutter mechanism 30 of the rotating shell 20 is pressed against the ground by the propulsion mechanism 18. The rotational force of the motor 34 is transmitted to the speed reducer 32, the torque is amplified, and the rotating part shell 20 is rotated via the pinion 37 and the pin rack 35. When the rotating part shell 20 rotates, first, the ground is excavated in a sawtooth shape by the roller bit 38 of the cutter part 30, and the surface irregularities are scraped by the drill bit 40. Thereby, the ground can be excavated in an annular shape.

  As described above, in the present embodiment, the protruding rib 39 is provided on the distal end surface portion 20A of the rotating portion shell 20 so as to extend in the circumferential direction. Since the rotary shell 20 is pressed forward, the excavated soil 82 generated by excavating the ground due to the rotation of the rotary shell 20 is formed between the projecting ribs 39 as shown in FIG. Get in. The excavated soil 82 that has entered between the projecting ribs 39 is held by the projecting ribs 39 in a state of covering the distal end surface portion 20A even when the rotating unit shell 20 rotates, and the rotating unit shells are covered. 20 and rotate.

  Here, since the cutter unit 30 is pressurized toward the ground, there is a risk that the rock will come into contact with the distal end surface 20A of the rotating shell 20 when excavating a strong rock. Further, the excavated soil generated by the rotation of the rotating shell 20 may include rocks that have not been crushed by the roller bit 38 or the drill bit 40. When such a rock collides with the tip surface portion 20A of the rotating part shell 20, the tip surface portion 20A may be damaged.

  However, in this embodiment, since the protruding rib 39 is attached to the front end surface portion 20A of the rotating part shell 20, the rock generated by rock or excavation contacts the earth and sand 82 held by the protruding rib 39. It becomes. Thereby, it can prevent that a rock mass and rock collide directly with 20 A of front end surface parts, and the cutter part 30 is damaged.

  When excavating the ground by rotating the rotating shell 20, the excavation direction of the excavator 10 can be adjusted by extending each of the front axial jacks 52 by different lengths. That is, for example, by increasing the extension length of the front axial jack 52 positioned below the apparatus, compared to the extension length of the front axial jack 52 positioned above the apparatus, The first fixed part shell 22 can be directed obliquely upward with respect to the second fixed part shell 24.

  Next, the front radial jack 54 is extended radially outward to press the surrounding ground. Then, the rear axial jack 50 is contracted while the reaction force is applied to the surrounding ground by the front radial jack 54. As a result, the third fixed portion shell 26 is drawn toward the first fixed portion shell 22. The excavator 10 can be advanced by repeating the above steps.

In addition, not only said method but the drilling apparatus 10 can also be advanced using the propulsion jack 57. FIG. That is, first, the front and rear radial jacks 54 and 56 are retracted. In this state, the propulsion jack 57 is extended by applying a reaction force to an inner formwork or the like attached in a tunnel that has already been excavated. Thereby, excavation apparatus 10 advances. Then, at least one of the front and rear radial jacks 54, 56 is extended radially outward to press the surrounding ground. Then, the propulsion jack 57 is retracted, and a new inner mold is attached at a position behind the propulsion jack 57.
The excavator 10 can also be propelled by repeating the above steps.

  Along with the above-described propulsion work and excavation work, excavated soil generated by the excavation work by the excavator 10 is sent to the rear of the apparatus.

  The excavated soil produced by excavating the ground with the cutter unit 30 is agitated with the water sprayed from the jet nozzle, and the fluidity is improved. Then, the excavated soil is accommodated in the chamber 20F in the rotating part shell 20 through the opening 36 formed in the distal end surface part 20A of the rotating part shell 20. Then, the excavated soil accommodated in the chamber 20F is discharged from the gap 20D to the inner space of the excavator 10 (that is, the inner side of the inner cylinder 22C).

  At this time, the closing plate 44 causes the gap 20D between the rear end of the inner cylindrical body 20C of the rotating portion shell 20 and the front end of the inner cylindrical body 22C of the first fixed portion shell 22 to be maximized in the circumferential direction. Since the portion from the lower part to the predetermined height is closed, the excavated soil in the chamber 20F rotated to the predetermined height is discharged into the inner space of the inner cylinder. As a result, the excavated soil carried to the inside of the apparatus accumulates downward, and the rear end of the inner cylinder 20C of the rotating part shell 20 and the front end of the inner cylinder 22C of the first fixed part shell 22 It is possible to prevent the gap 20D between them from being closed.

  In parallel with the work of excavating the ground in an annular shape by the excavator 10, the ground inside the portion excavated in an annular shape by the excavator 10 is excavated by the breaker 62.

  Next, a method for conveying excavated soil generated by excavating the ground to the apparatus construction method will be described. FIG. 11 is a schematic diagram for explaining a method of transporting excavated soil.

  As described above, when the ground is excavated in an annular shape by the cutter unit 30, the excavated soil 110 including rocks and the like generated by the excavation is accommodated in the rotating unit shell 20, and is closed by the closing plate of the gap 20D. It falls from a portion that is not present and is discharged into the inner space of the excavator 10.

  As described above, since the trajectory through which the roller bit 38 passes is a concentric circle having substantially equal intervals (for example, about 8 cm) in the radial direction, the size of the excavated soil 110 thus discharged from the rotating portion shell 20 is as follows. It is about 8 cm. And the excavated soil 110 discharged | emitted from the rotation part shell 20 accumulates on the excavated soil receiving plate 100, and when excavation advances, it is sent to the sieving mechanism 102.

  Since most of the excavated soil 110 sent to the sieving mechanism 102 has a small diameter, most of the excavated soil 110 falls through the sieving mechanism 102 and is further guided by the hopper 104 and falls on the conveyor 81.

  Thus, most of the excavated soil 110 discharged from the rotating shell 20 passes through the sieving mechanism 102, falls on the conveyor 81, and is conveyed to the rear of the apparatus by the conveyor 81.

  Further, the cylindrical ground 120 left after the ground is excavated in an annular shape by the cutter unit 30 is crushed by the breaker 62. In addition, the excavated soil generated by crushing the ground 120 with the breaker 62 in this way includes rocks having a diameter of about 1 m. Then, the excavated soil generated by crushing the ground 120 with the breaker 62 is sent to the crusher 106 and finely crushed to a diameter of 25 cm or less. The excavated soil crushed by the crusher 106 in this way falls onto the conveyor 81 and passes through the sieving mechanism 102 and is sent to the rear together with the excavated soil dropped onto the conveyor 81. At this time, excavated soil generated by crushing the ground 120 with the breaker 62 may fall onto the conveyor 81 through the sieving mechanism 102.

  Furthermore, when excavation progresses and the excavator 10 moves forward, the end (rear end) of the ground 120 remaining in the columnar shape reaches the crusher 106. As described above, the crusher 106 has a front end that is approximately the same height as the inner cylinder 20C of the rotating shell 20 and is inclined so that the rear is positioned higher than the front. When the end (rear end) of the columnar ground 120 reaches the crusher 106, the lower end of the columnar ground 120 is crushed by the crusher 106, and the crushed excavated soil falls onto the conveyor 81.

  If the excavated soil 110 discharged from the rotating shell 20 contains large rocks or the like, the excavated soil generated by crushing the columnar ground 120 may be fed into the crusher 106. .

  The excavated soil that has fallen on the conveyor 81 in this manner is conveyed to the rear of the apparatus by the conveyor 81 and discharged out of the tunnel by a dump truck or the like.

  According to the present embodiment, the tip surface portion 20A of the rotating part shell 20 is flat, and the projecting rib 39 is provided on the tip surface part 20A of the rotating part shell 20, so that the earth and sand generated by the excavation work can be removed. The rotating part shell 20 is held in a state of covering the front end face part 20A. Thereby, it can prevent that the rock produced by the bedrock and excavation work collides directly with the cutter part 30 (tip surface part 20A), and the cutter part 30 is damaged. And according to this embodiment, without providing the thickness of 20 A of front-end | tip surface parts of the rotation part shell 20, or changing a material into a high intensity | strength, only providing the protruding rib 39, Since the collision of rocks can be prevented, the cutter unit 30 can be prevented from being damaged at low cost.

  Further, in the present embodiment, since the projecting rib 39 is provided so as to extend in the radial direction, that is, across the rotational direction of the cutter unit, the earth and sand are reliably retained even when the cutter unit 30 rotates. be able to.

  In the present embodiment, the protruding rib 39 is provided so as to extend straight in the radial direction. However, the present invention is not limited to this, and if the earth and sand can be reliably held when the cutter unit 30 rotates, It may be a curved shape.

  In the present embodiment, the tip surface portion 20A is provided with a rib-like protrusion, but the present invention is not limited to this. For example, the earth and sand can be held in a state where the tip surface portion is covered by providing a plurality of rectangular projections or the like.

  In the present embodiment, the cylindrical excavator provided with an annular cutter head has been described. However, the present invention is not limited thereto, and the present invention can also be applied to a columnar excavator provided with a circular cutter head.

DESCRIPTION OF SYMBOLS 10 Excavator 12 Shell 14 Excavation mechanism 16 Excavation soil carrying-out mechanism 18 Propulsion mechanism 20 Rotating part shell 20A Front end surface part 20B, 22B, 24B, 26B Outer cylinder 20C, 22C, 24C, 26C Inner cylinder 20D Gap 20E Space 20F Chamber 22 First fixed part shell 24 Second fixed part shell 26 Third fixed part shell 30 Cutter part 32 Reducer 33 Ring 34 Motor 35 Pin rack 36 Opening 38 Roller bit 39 Projecting rib 40 Drilling bit 42 Plate 44 Closure Plate 50 Rear Axial Jack 52 Front Axial Jack 54 Front Radial Jack 56 Rear Radial Jack 57 Propulsion Jack 62 Breaker 70 Base 81 Conveyor 82 Excavated Soil (Sand)
DESCRIPTION OF SYMBOLS 100 Excavation soil receiving plate 102 Sieving mechanism 104 Hopper 106 Crusher 110 Excavation soil 120 Ground

Claims (4)

A cylindrical or cylindrical tunnel excavator for excavating a tunnel in the ground,
A cutter head for excavating the ground by rotating around the central axis of the tunnel excavator is provided at the tip,
The cutter head is
A drill bit provided on a flat tip surface;
A protruding portion that is provided so as to protrude from the tip surface, and holds the earth and sand so that the earth and sand generated by the excavation bit shaving the ground when the cutter head rotates is covered with the tip surface. A tunnel excavator characterized by comprising.   The tunnel excavation device according to claim 1, wherein the projecting portion includes projecting ribs provided to extend in a radial direction. The tunnel excavator is cylindrical,
The tunnel excavation device according to claim 1, wherein the cutter head has an annular shape.   The tunnel excavation device according to claim 1, wherein a height of the protruding rib from the tip surface is lower than a height of the excavation bit from the tip surface.

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