JP3220382B2 - Shield excavator cutter head - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cutter head of a shield excavator capable of removing obstacles such as a retaining wall such as a sheet pile and a pile, etc. existing on the way of excavation.

[0002]

2. Description of the Related Art When an obstacle such as a foundation pile is reached while a tunnel is being excavated by a shield excavator, an obstacle cannot be cut or removed with a drill bit protruding from a cutter head. After stopping the operation, digging a shaft from the ground to remove obstacles and removing workers by hand from the inside of the aircraft to the face side are performed, but in the former method to excavate the shaft from the ground In addition to adversely affecting the surrounding environment and traffic, as well as buried pipes, if the obstacle is a foundation pile for a structure, excavation of a horizontal shaft from the vertical shaft to the foundation pile is required, and a long construction period is required. And the cost increases. On the other hand, the latter method requires auxiliary methods for ground stability such as ground freezing method and jet grout method so that safe work on the face is possible. There is a problem in that the use of fire for cutting piles is extremely dangerous work, and in addition, the working environment at the face is poor and the efficiency is reduced.

[0003] For this reason, the applicant of the present invention has reported that
As described in Japanese Patent No. 9555, a cutter head of a shield excavator having a ground excavation bit and a bit capable of cutting an obstacle such as a pile has been developed. In this cutter head, a plurality of fixed arm members are radially arranged from the rotation center of the cutter head main body, and a plurality of core cutters are mounted on these fixed arm members, and excavation of these core cutters by rotation of the cutter head main body. The moving trajectory is arranged in an arrangement such that the cutter head body contacts or partially overlaps in the radial direction, and these core cutters are configured to be able to protrude and retract from the front surface of the cutter head.
The roller cutter is provided on a fixed arm member different from the fixed arm member provided with the core cutter.

When the shield excavator reaches an obstacle, the rotation of the cutter head is stopped, and then the core cutter is protruded while rotating to excavate an annular groove having the same sectional shape as the core cutter in the obstacle. After excavation, the cutter head is rotated by an angle corresponding to the diameter of the core cutter, and the next annular groove is excavated in contact with the groove again, and this operation is repeatedly performed by each core cutter to continuously form a plurality of rows on the obstacle. After excavating the annular groove, the part surrounded by the groove is rotated by a cutter head, and cut and removed by a roller cutter disposed on another fixed arm member. Obstacles are cut and removed by sequentially and repeatedly performing the cutting with the above.

[0005]

However, by rotating the core cutter provided on the fixed arm member of the cutter head main body while rotating the cutter head without rotating the cutter head, an annular groove is excavated in the obstacle. Therefore, each core cutter requires a rotary drive mechanism and a mechanism for moving the entire cutter in the front-rear direction, which not only complicates the entire apparatus, but also excavates a series of annular grooves by the core cutter. The head must be rotated by an angle equal to the diameter of the core cutter, and furthermore, since the core cutter cannot be cut by merely excavating the groove, the cutting work by the roller cutter is required as described above after excavation. There is a problem that work efficiency is reduced.

Further, during the cutting operation by the roller cutter, the obstacle portion to be cut is completely exposed and the exposed portion is uniformly cut by the roller cutter. If the impact force at the time of cutting is large, there is a possibility that an obstacle may vibrate to lower the cutting efficiency or make cutting impossible. The present invention has been made in view of such a problem, and provides a cutter head of a shield excavator capable of smoothly and reliably cutting and removing obstacles such as a retaining wall such as a sheet pile and a pile. It is the purpose.

[0007]

The cutter head of the shield excavator of the present invention to achieve, there is provided a solution for the above object is achieved by a cutter head which is rotatably disposed in the opening front end of the shield excavator, the outer peripheral portion Rotating with outer ring
Centrally supported rotatably by shield excavator bulkhead
Arrange the center shaft, in front of this center shaft
Gear box that can rotate around the center shaft around the end
And a cylindrical body fitted externally to the gear box so as to be slidable back and forth.
The surface of the cylindrical body opposite to the outer peripheral ring is
The inner and outer ends are centered on the outer circumference of the cylinder and the outer circumference
Attached to each ring and constant height in the length direction
Fixed arms holding the drill bit
It is moved back and forth by the backward movement means and spirally wound on its outer peripheral surface.
Cutting bit against the fixed arm drill bit
Radiating with a rotating arm that can move forward and backward
Bevel gear fixed to the inner end of this rotary arm
Mesh with the bevel gear fixed to the front end of the center shaft
To transmit the rotation of the center shaft to the rotating arm.
And the front end of the center shaft
Fixed head with drill bit protruding forward
To the fixed head
It has a structure with a movable head with a retractable cutting bit.
You.

[0008]

[Function] When excavating the ground on the planned tunnel line using a shield excavator, the spiral cutting bit is retracted backward from the excavating bit protruding from the fixed arm by retracting the rotating arm. Keep it in a state.
Similarly, the movable head is retracted with respect to the fixed head provided at the front end of the center shaft, and the cutting bit protruding from the movable head is immersed backward from the drill bit protruding from the fixed head. Leave it in the state. The operation of retracting the rotating arm can be performed by contracting the jack for moving the center shaft back and forth and the jack connected to the bearing member of the rotating arm. In this state, the ground is excavated with the excavation bit protruding from the fixed arm by propelling the shield excavator while rotating the cutter head.

Next, when the vehicle hits an obstacle such as a sheet pile or a pile during the excavation, the rotary arm is advanced by a jack, and the spiral cutting bit is moved forward with respect to the excavation bit protruding from the fixed arm. To protrude. Also,
The movable head is also moved forward so that the cutting bit protrudes forward from the drill bit on the fixed head, and the shield drilling machine is propelled while rotating the cutter head and the center shaft, thereby obstructing the obstacle by the cutting bit. To remove.

[0010] The cutting of an obstacle is first performed by a cutting bit on the tip side of the movable head projecting forward. That is, the cutting bit projecting from the tip of the movable head first hits the obstacle, and the cutting bit drills a small-diameter hole in the obstacle. If the movable head is further advanced while rotating from this state, obstacles will be created while gradually cutting the small-diameter hole into a conical shape in the diameter-expanding direction with the cutting bit protruding from the inclined front end face of the movable head. Be cut.

Further, following the cutting bit protruding from the movable head, an obstacle is formed by the spiral cutting bit of the rotary arm radially disposed in the extension direction from the inclined end side of the movable head. Cutting is performed. That is, when the rotary arm is rotated at high speed through the meshing bevel gear while rotating the rotary arm around the center shaft by the rotation of the cutter head, the rotary arm reaches from the opening peripheral edge of the hole cut by the movable head to the outer peripheral ring. An obstacle corresponding to the portion is cut by the spiral cutting bit of the rotary arm, and a portion corresponding to the size of the cutter head is cut off. The shield excavator is propelled in synchronization with the cutting of the obstacle by the cutting bit.

In this way, the shield excavator cuts off the obstacle portion facing the cutter head by the cutting bit protruding from the movable head and the spiral cutting bit integrally provided on the outer periphery of the rotary arm. After passing through, the movable head with the cutting bit provided at the front end of the center shaft is immersed from the digging bit of the fixed head, and the rotating arm is moved to the position where the spiral cutting bit immerses behind the digging bit of the fixed arm. Retreat until

Thereafter, the tunnel is constructed while the ground is excavated by the excavation bit of the fixed head and the fixed arm by propelling the shield excavator while rotating the cutter head. In addition, excavated earth and sand and cut pieces of obstacles are taken into the machine through the space between the fixed arms adjacent to each other in the circumferential direction and the space between the fixed arm and the rotating arm.
Discharge through the tunnel.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to the drawings, a specific embodiment of the present invention will now be described. In FIG. 1, reference numeral 1 denotes a shield excavator, which has a substantially same diameter as the skin plate 1a at the opening front end of the skin plate 1a. The cutter head A is rotatably supported by a partition 1b integral with a skin plate 1a which is stretched at an appropriate distance behind the cutter head A.

The cutter head A has a center shaft 2 disposed at the center, an outer peripheral ring 3 disposed on the outer peripheral side close to the front end of the skin plate 1a, and a center shaft surrounding the front end of the center shaft 2. A cylindrical body 18 for receiving the gear box 4 disposed on the shaft 2 slidably back and forth;
As shown in FIG. 2, a plurality of fixed arms 5 and rotating arms 6 radially arranged around the center shaft 2 between the opposing surfaces of the outer ring 18 and the outer peripheral ring 3, and forwardly toward the front end of the center shaft 2. A fixed head 7 with a drill bit protruding in a mountain shape, and a movable head 8 with a cutting bit having substantially the same shape as the fixed head 7 and capable of moving forward and backward with respect to the fixed head 7. Have been.

In the cutter head A, the plurality of fixed arms 5 and the rotating arms 6 radially arranged from the center shaft 2 are arranged at regular angular intervals around the center shaft 2 in the circumferential direction. However, two rotating arms 6 are arranged in the figure in the diameter direction of the outer peripheral ring 3, and two fixed arms 5 are arranged between these rotating arms 6, 6. The fixed arm 5 is formed in a rectangular shape having a fixed width and a fixed length, and its inner and outer ends are fixed to the outer peripheral surface of the cylindrical body 18 and the outer peripheral ring 3, respectively, and are fixed along both long side edges of the front surface. Earth and sand excavation bits 9 having a height are fixed at predetermined intervals in the length direction. In addition, the outer peripheral ring 3 is the shield excavator 1
Of the skin plate 1a. A sediment intake opening 10 is provided between the adjacent fixed arms 5 and 5 and between the fixed arm 5 and the rotating arm 6.

On the other hand, the rotary arm 6 is formed in a cylindrical shape having a circular cross section, and a helical cutting bit 11 continuous over substantially the entire length is integrally attached to an outer peripheral surface thereof. Specifically, a spiral projecting wall 12 is fixed to the outer peripheral surface of the rotating arm 6, and this projecting wall is
A cutting bit 11 is formed or fixed on the top end face of the 12.
At the rear side of the rotary arm 6, there is provided a support member 13 whose inner and outer ends parallel to the longitudinal direction of the rotary arm 6 are connected and fixed to the opposing surface of the cylindrical body 18 and the outer peripheral ring 3. A movable plate 16 having bearing members 14 and 15 rotatably supporting the inner and outer ends of the rotary arm 6 is provided between the member 13 and the rotary arm 6. The jacks 17 fixed at both ends are integrally connected to rod ends of the jacks 17 so that the entire rotary arm 6 is moved back and forth by expansion and contraction of the jack 17.

The inner end of the rotary arm 6 has a gear box 4 inserted through a bearing member 14. A bevel gear 19 is fixed to the inner end of the gear box 4, and this bevel gear 19 is attached to the front end of the center shaft 2. It is engaged with the fixed bevel gear 20. The center shaft 2 is rotatably inserted into and supported by a bearing member 21 fixed to the center of the gear box 4. Further, the gear box 4
The front end of the center shaft 2 is provided with a bearing member 23 fixed to the center of the cover plate 22 and a bearing member 24 fixed to the center of the partition 1b of the shield excavator 1. And the rear part are inserted rotatably. And
The gear box 4 is fitted inside the cylindrical body 18 so as to be slidable back and forth.

Another gear box 25 is fixed to the center of the rear surface of the partition wall 1b of the shield excavator 1.
A jack 26 for moving the center shaft 2 back and forth in the longitudinal direction is mounted on the rear surface of the rotary arm 6. The jack 26 and the jack 17 for moving the bearing members 14 and 15 of the rotary arm 6 back and forth serve as a means for moving the rotary arm 6 back and forth. Make up. On the other hand, the rotation driving means of the rotary arm 6 has a drive motor 27 mounted on the rear surface of the gear box 25, and a rotation shaft of the motor 27 protrudes into the gear box 25, and a small-diameter gear 28 fixed to the protruding end thereof has a center shaft The large-diameter gear 29 fitted to the rear portion of the center shaft 2 so as to be movable back and forth by spline fitting.
, And the rotation of the drive motor 27 is
And transmitted to the rotary arm 6 via the meshing bevel gears 19 and 20.

At the front end of the center shaft 2 protruding from the cover plate 22 of the gear box 4 containing the meshing bevel gears 19 and 20, a disk-shaped cutter mounting base 30 is fixedly mounted.
The rear end face of the fixed head 7 projecting forward in a mountain shape is fixed to the front surface of the head, and the mountain-shaped inclined front end face of the fixed head 7 is soiled at small intervals from the front end to the outer end. A drill bit 31 protrudes. On the other hand, like the fixed head 7, the movable head 8 is made of a plate material projecting in a mountain shape toward the front, and the tip and the inclined front end face are provided with obstacle cutting bits 32 at small intervals. I have.

The fixed head 7 and the movable head 8 intersect each other in a front cross shape, and the movable head 8 is disposed at the center of the fixed head 7 so as to be able to move back and forth. Further, the rear end of the movable head 8 is integrally connected to the front end of the piston rod of the jack 33 mounted on the front end of the hollow inside of the center shaft 2. Fix the cutting bit 32 to the drill bit 31 of the head 7
To the front and rear.

The cutting bit 32 on the outermost end of the inclined end surface of the movable head 8 is connected to the inner end of at least one of the spiral cutting bits 11 provided on the two rotating arms 6. The outer peripheral portion of the cutting movement locus by the cutting bit 32 on the outermost end side of the movable head 8 is positioned in front of the inner periphery of the cutting movement locus by the cutting bit portion on the inner end side of the spiral cutting bit 11. It is configured to contact or overlap with.
Further, a bearing member which supports these rotary arms 6, 6
The helical cutting bit 11 which is provided at a position shifted from each other in the longitudinal direction of the rotary arm 6 and is separated by the bearing members 14 and 15 is continuous by the helical cutting bit 11 of one of the rotary arms 6. It is configured so that it can be cut as desired.

On the other hand, the fixed arm 5 of the cutter head A
The front end of the horizontal arm member 34 is fixed to the outer end of the horizontal arm member and the outer end of the support member 13 of the rotating arm 6.
A large- and small-diameter ring body in which the rear end surface is fixed to the front surface of a ring-shaped end plate 35, and this ring-shaped end plate 35 is fixed to the outer periphery of the front surface of the partition wall 1b of the shield excavator 1 together with the rear end of the horizontal arm member Three
It is rotatably supported between bearings 6 and 37 via bearings 38 and 39.

The rotary drive mechanism of the cutter head A has a drive motor 40 mounted on the rear surface of the partition wall 1b of the shield excavator 1 and a small gear 41 fixed to the rotation shaft of the drive motor 40, which is provided on the ring-shaped end plate 35. The internal gear 42 is fixed to the rear end face. The rear surface of the cutter head A and the partition wall
Sediment intake chamber 43 formed in the space between the surfaces facing 1b
A screw conveyor (not shown) is installed inside the machine, and the opening at the lower inclined end of the screw conveyor faces the lower end of the earth and sand intake chamber 43.

The shield excavator 1 configured as described above has
The segment (not shown) assembled in the tail portion of the skin plate 1a moves forward by supporting a reaction force and operating a propulsion jack (not shown), and further rotates the cutter head A by driving the drive motor 40. By rotating the center shaft 2 through the meshing gears 28 and 29 by driving the drive motor 27, the fixed head 7 and the fixed arm 5 of the center shaft 2 of the cutter head A are rotated.
The tunnel will be constructed while excavating the ground with the excavating bits 9 and 31 protruding at the same time. The excavated earth and sand is taken into the intake chamber 43 from the earth and sand intake opening 10, is carried out into the machine by a screw conveyor, and is discharged through a tunnel by a toro or the like. In the case of earth and sand excavation, excavation can be performed without rotating the center shaft 2 and the fixed head 7.

When the ground is excavated as described above, the movable head driving jack 33 is contracted, and the cutting bit 32 projecting from the movable head 8 is projected from the fixed head 7. A jack immersed backward from the drill bit 31 and further supports the rotating arm 6 via bearing members 14 and 15 and a movable plate 16.
As shown in FIG. 1, the helical cutting bit 11 projecting from the rotating arm 6 is protruded from the fixed arm 5 by contracting the rotating arm 17 and retracting the entire rotating arm. The center shaft 2 is retracted integrally with the gear box 4 by being retracted backward from the bit 9 and contracting the center shaft front and rear movement jack 26, and the bevel gear 1 in the gear box 4 is retracted.
9. Keep 9 and 20 engaged.

Next, as described above, the earth and sand excavation bits 9, 31
When the shield excavator 1 moves forward while excavating the tunnel and applying segment lining to the excavated wall surface, and hits an obstacle such as a sheet pile or a pile driven into the ground during the excavation, the movable head The driving jack 33 is extended to move the movable head 8 forward, and the cutting bit 32 projecting from the front inclined surface is projected from the fixed head 7 as shown by a two-dot chain line in FIG. Projecting from the drill bit 31 that is
By extending the center shaft 2 to move the center shaft 2 forward with the gear box 4 and extending the jacks 17, 17 to advance the entire rotary arm 6, the spiral projecting from the rotary arms 6, 6 is extended. The cutting bit 11 is made to project forward from the excavating bit 9 protruding from the fixed arm 5. In this state, an obstacle is cut and removed by the cutting bits 11 and 32 while rotating the cutter head A.

A long hole (not shown) long in the front-rear direction is formed in the side surface of the gear box 4, and the inner end of the rotary arm 6 is inserted through the long hole so as to be slidable back and forth. The shaft 2 is configured to be rotatable only without being configured to be movable back and forth in the longitudinal direction,
When the bevel gear 19 fixed to the inner end thereof is engaged with the bevel gear 20 fixed to the front end of the center shaft 2, the spiral cutting bit 11 of the rotating arm 6 is fixed to the fixed arm 5.
When the rotary arm 6 is retracted, the spiral cutting bit 11 is fixed to the fixed arm 5 when the rotary arm 6 is retracted.
May be configured to be immersed rearward with respect to the excavating bit 9. With this configuration, even if the center shaft 2 is rotated during the excavation of the ground, the rotation is not transmitted to the rotary arm 6, so that the rotation of the center shaft 2 can be efficiently performed and the gear box 4 can be moved relative to the cylindrical body 18. Thus, the gear box 4 and the cylindrical body 18 can be integrated.

The method of cutting and removing obstacles using the cutting bit 32 of the movable head 8 and the cutting bit 11 of the rotary arm 6 will be described in more detail. First, the center shaft 2 is rotated and the movable head driving jack 33 is rotated. When the movable head 8 is advanced by extending the cutting head 32, the cutting bit 32 projecting from the front inclined surface of the movable head 8
It protrudes forward from 31 and its sharp end pierces an obstacle to drill a small-diameter hole. When the movable head 8 is further advanced from this state, the cutting bits 32 sequentially projecting from the inner end to the outer end on the inclined front end face of the movable head 8 are provided.
Thus, the obstacle is cut while the small-diameter hole is gradually cut and expanded in a conical shape in the diameter-expanding direction.

In this way, when a hole having a size equal to the outer diameter of the movable head 8 is cut in the obstacle by the cutting bit 32 of the movable head 8, the cutting by the outermost end cutting bit 32 of the movable head 8 is performed. Then, with the rotation of the cutter head A, the cutting hole is formed by the spiral cutting bit 11 of the rotary arm 6 so as to be continuous with the outer periphery of the cutting movement locus of the outermost cutting bite 32 in accordance with the propulsion of the shield excavator 1. Is further cut into a hole whose diameter has been increased to the outer diameter of the outer peripheral ring 3.

That is, the entire rotary arm 6 is advanced by extending the jacks 17, 17 with the advancement of the center shaft 2, and in this state, the drive motors 27, 40 are driven to rotate the center shaft 2 and the cutter head A. When the shield excavator 1 is propelled while rotating, the rotation of the cutter head A causes the rotating arm 6 to pivot around the center shaft 2 and the rotation of the center shaft 2 to rotate through the meshing bevel gears 19 and 20. The rotating arm 6 rotates at a high speed, and an obstacle is cut by the spiral cutting bit 11 protruding from the outer peripheral surface of the rotating arm 6 to form an enlarged hole through which the cutter head A can pass. At this time, the entire rotary arm is advanced integrally with the center shaft 2 in accordance with the amount of wear of the spiral cutting bit 11 and the spiral cutting bit 11 is advanced.
Adjust the protrusion amount of 11. The cut pieces of the obstacle B are taken into the intake chamber 43 from the earth and sand intake opening 10 and discharged backward by the screw conveyor, similarly to the excavated earth and sand.

When the shield excavator 1 passes through the obstacle while cutting off the obstacle portion facing the cutter head A, the movable head 8 provided at the front end of the center shaft 2 is retracted by the jack 33 so as to be moved. Cutting bit 32
Is immersed from the excavation bit 31 of the fixed head 7 and the rotary arm 6 is retracted so that the helical cutting bit 11 is immersed from the excavation bit 9 of the fixed arm 7. In this state, the cutter head A is rotated. Shield excavator 1
And a tunnel is constructed while excavating the ground by the excavation bits 9 and 31 protruding from the fixed arm 5 and the fixed head 7. In addition, the opening edge of the excised obstacle B is
It is integrated with the segment lining of the tunnel and supported by the tunnel portion.

In the above embodiment, the spiral cutting bit 11 protruding from the rotary arm 6 is formed to have the same diameter over the entire length of the rotary arm 6, but from the inner end side to the outer end side of the rotary arm 6. The diameter of the movable head 8 may be gradually reduced toward the movable head 8.
After the obstacle is cut and expanded in a conical shape by the cutting bit 32, the rotary arm 6 can be further cut and expanded continuously from the inner end side to the outer end side by the cutting bit 11.

Similarly, the rotary arm 6 is configured to move back and forth while maintaining the state in which the rotary arm 6 is directed in a direction perpendicular to the center shaft 2. However, in the inner and outer jacks 17 supporting the rotary arm 6, The rotary arm 6 may be inclined obliquely rearward and outward from the center shaft 2 side by largely contracting the outer jack 17, and the cutting may be performed in such a manner as to cut and expand the obstacle in the same manner as described above.

[0035]

As described above, according to the cutter head of the shield excavator of the present invention , when excavating a tunnel, the movable head and the rotating arm are moved backward with respect to the fixed head and the fixed arm, respectively. The tunnel is built while excavating the ground with the excavation bit by immersing the obstacle cutting bit protruding from the head and the rotating arm behind the earth and sand excavation bit protruding from the fixed head and the fixed arm. Can also be used, and while excavating,
When hitting an obstacle such as H steel or a pile, the movable bit is moved forward and the entire movable arm is advanced, so that the cutting bit is removed from the excavated bit protruding from the fixed head and the fixed arm. By protruding forward, obstacles can be cut by these cutting bits.

At this time, the movable head is formed in a mountain shape toward the front, and a cutting bit is protrudingly provided on the front inclined surface thereof. A small-diameter hole can be drilled, and from that state, the small-diameter hole can be cut and expanded in a conical shape with a cutting bit projecting from the front end inclined surface by advancing the movable head. Further, following the enlarged cutting by the cutting bit on the movable head, the cutting portion of the obstacle can be cut and removed by the spiral cutting bit protruding from the rotary arm while continuously expanding the cut portion.

As described above, the obstacle is cut in a cone shape by the cutting bit of the movable head and then cut in the radially expanding direction by the rotating arm. It can cut and remove smoothly and reliably with a small cutting force, and when cutting obstacles such as H steel and sheet pile, the obstacles are supported in the ground except for the cutting end face of the obstacle by the cutting bit. Therefore, it is possible to efficiently cut and remove only the portion facing the cutter head in a state where the obstacle portion to be cut is firmly fixed to the ground without rotating together with the cutter head. In addition, the construction period of the tunnel can be shortened.

Further , since the rotation of the center shaft is transmitted to the rotary arm via the meshing bevel gear, the rotation drive from the center shaft is reliably transmitted and the rotary arm is rotated at high speed. Obstacles can be efficiently cut. In addition , the entire rotary arm can be smoothly moved back and forth , and the rotary arm can be moved forward according to the amount of wear of the spiral cutting bit. In addition, the rotary arm can be inclined obliquely rearward. As a result, the obstacle can be cut and spread efficiently.

[Brief description of the drawings]

FIG. 1 is a partial longitudinal sectional simplified side view of a shield excavator provided with a cutter head of the present invention,

FIG. 2 is a front view of the cutter head,

FIG. 3 is a sectional view of a rotating arm portion.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shield excavator 2 Center shaft 3 Outer ring 4 Gear box 5 Fixed arm 6 Movable arm 7 Fixed head 8 Movable head 9 Drilling bit 11 Spiral cutting bit 13 Support member 14, 15 Bearing member 17 Jack 19, 20 Bevel gear 31 drill bit 32 cutting bit

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-64-24993 (JP, A) JP-A-5-133190 (JP, A) JP-A-5-106395 (JP, A) 185789 (JP, U) Japanese Utility Model 4-112992 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) E21D 9/08

Claims (1)

(57) [Claims] 1. A cutter head rotatably disposed on a front end side of an opening of a shield excavator, wherein an outer peripheral ring is provided on an outer peripheral portion.
And a shield excavator bulkhead at the center of rotation
A rotatable center shaft is installed on the
Around the front end of the center shaft
Gear box that can rotate around and this gear box can slide back and forth
An externally fitted cylinder is provided, and the outer peripheral surface of the
On the center shaft center
The ends are integrally fixed to the outer peripheral surface of the cylindrical body and the outer peripheral ring, respectively.
And fixing a drill bit with a constant height in the length direction.
It is moved back and forth by several fixed arms and
The cutting bit spirally wound around the outer peripheral surface of the
To be able to move forward and backward with respect to the drill bit
The rotating arm that is
Bevel gear fixed to the inner end is fixed to the front end of the center shaft.
Meshes with the beveled gear and rotates the center shaft.
To the transfer arm.
Excavation protruding forward at the front end of the center shaft
A fixed head with a bit is provided integrally with this fixed head.
Movable head with cutting bit that can move back and forth with respect to the part
Shield excavator cutter head, characterized in that it is disposed.