JP2824228B2 - Ball type shield machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates] also relates to a ball-type shield machine, relates to a shield machine having the advance direction drilling in Japanese to be changed to a desired direction.

[0002]

2. Description of the Related Art When excavating various underground passages such as a water pipe, a sewer pipe, a common ditch, and a subway tunnel, a shield machine is applied. A typical shield machine is an excavator having a cutter disk provided with a plurality of cutter bits, an erector attached to the main body frame for constructing a segment, and a cylindrical rear machine connected to the main body frame of the excavator. It has a trunk, a plurality of shield jacks for generating excavation thrust, a fluid-type earth and sand discharge mechanism or a conveyor-type earth and sand discharge mechanism for fluidizing and discharging earth and sand.

In the shield machine described above, the direction of excavation cannot be freely changed, and the direction of excavation can be changed only about ten and several degrees. Therefore, the direction of the horizontal shaft is changed at a steep angle or the direction of the horizontal shaft is changed by 90 degrees. And it is not possible to change direction from a shaft to a horizontal shaft. However, recently, when excavating an underground passage directly under a road, the excavation direction is changed at a 90-degree direction at the intersection of the road, or the excavation direction is changed at a steep angle at a place where it interferes with the foundation of the building or the like. In many cases, the direction of a vertical shaft is changed from a vertical shaft to a horizontal shaft by 90 degrees.

Therefore, in a shield machine described in Japanese Patent Application Laid-Open No. 63-251598, a front body is formed into a partially spherical body, and a cutter having a partial spherical surface smaller than a hemisphere at the front end of the front body. A disk is provided, a plurality of cutter bits are provided on a partially spherical front end surface and a cylindrical outer peripheral surface of the cutter disk, and a front portion of the rear body is formed into a partially spherical body,
Through the intermediate torso between the front and rear trunks (connected to the front torso via the spherical seat and connected to the rear torso via the spherical seat), the front torso relative to the intermediate torso In addition to being configured to be able to bend by 27 degrees, the intermediate body is configured to be able to bend by about 17 degrees with respect to the rear body, so that it can be excavated along an arc-shaped curve.

On the other hand, in the excavation room rotary type shield excavator described in Japanese Patent Application Laid-Open No. 4-140396, a spherical excavation room having a smaller diameter than the cylindrical body is provided at the tip of the cylindrical body of the outer shield excavator. A built-in shield excavator is provided in the spherical excavation room so as to be rotatable together with the spherical excavation room, an opening through which the built-in shield excavator can pass is formed on the side of the cylindrical body, and the external shield excavator and the built-in shield excavator are coaxial. In the placed state, the shaft is excavated by both excavators, and at the end of the shaft, the built-in shield excavator is turned 90 degrees together with the spherical excavation chamber, and then the horizontal shaft is excavated by the built-in shield excavator. It is.

[0006]

DISCLOSURE OF THE INVENTION The aforementioned JP-A-63-25
In the shield machine described in No. 1598, the excavation direction can be changed only along the arc-shaped curve, so that the horizontal shaft can be turned 90 degrees or the vertical shaft can be turned to the horizontal shaft. That the excavation target is severely restricted because the direction of the steep angle cannot be changed, and the structure of the rear and intermediate trunks is complicated, regardless of the structure of the front trunk.
There is a problem in that the structure is complicated and the number of jacks for changing directions is increased, which is disadvantageous in manufacturing cost.

[0007] The drilling room rotary shield machine described in Japanese Patent Application Laid-Open No. 4-140396 is basically intended to change the direction from a shaft to a horizontal shaft, and the excavation direction is 90 degrees. It is only possible to convert, and it is not possible to change the direction at any angle.Because the excavation diameter of the built-in shield excavator is smaller than the excavation diameter of the external shield excavator, it is not possible to change the excavation direction while maintaining the excavation diameter, There is a problem that the direction change in the excavation direction can be performed only once, and the direction change over a plurality of times cannot be performed.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a shield machine capable of changing the direction of a steep excavation, enabling a change in the direction of a digging to a desired direction, a plurality of digging directions. The conversion is made possible, the excavation diameter is made the same before and after the excavation direction conversion, and the structure of the shield excavator is prevented from becoming complicated.

[0009]

A ball-type shield excavator according to claim 1 excavates a tunnel-shaped underground passage.
And a cylindrical rear trunk connected to the rear end of the machine
, Erector, and multiple shields for generating excavation thrust
A shield machine with a jack,
Cutter frame for installing multiple cutter bits
Is along the inside of a hemisphere of approximately the same diameter as the drilling diameter.
It has a semi-hemispherical shape and partitions the chamber of the machine.
The partition wall is a predetermined length on the rear end side of the cutter frame.
An annular tapered wall member extending along the vicinity of the inside of the
An annular tapered wall member having a smaller diameter toward the side;
The lud jack is located near the inside of the annular tapered wall member and thereafter.
It is arranged in an inclined posture over the space on the side, and each shield
The front end of the jack body of the jack is
The inclination angle of the inclination posture is set at a position near the front end of the paper wall member.
The pin is variably connected and the rear trunk is the rear end of the machine.
Are connected so as to be able to be disconnected.

[0010] The cutter frame of the excavator has an
Almost hemispherical configuration along the inside of a hemisphere of equal diameter
Therefore, when changing the direction of the excavation, the excavator is rotated around the center of the hemisphere in a state where the connection of the rear trunk is released, so that the excavator is moved in a desired direction. The digging can be performed by changing the digging direction to the desired direction.

Therefore, the direction of excavation can be freely changed to a gentle angle or a steep angle, the direction can be changed to a desired direction, and even if the direction is changed, the excavation diameter remains unchanged. Since the direction can be changed, the direction can be changed several times. Moreover, if the associated equipment such as an erector and a shield jack is arranged so as to be accommodated in the spherical surface including the hemisphere, the excavator can be rotated about the center of the hemisphere as a rotation center. The structure is not so complicated. Connect each shield jack to the cutter frame
Extending along the inside of the predetermined length on the rear end side of the
The space near the inside and behind the annular tapered wall member whose diameter is reduced
Each shield jack must be long to arrange
Thus, the stroke can be increased .

[0012] The ball type shield machine according to claim 2 is a contractor.
The invention according to claim 1, wherein each of the shield jacks has a jack.
The rocking body can be driven to rock through the trunnion support.
A hydraulic cylinder for movement.
You. The excavator is moved forward by multiple shield jacks.
The angle of inclination of each shield jack changes,
Swing the shield jack with a swing hydraulic cylinder.
By changing the inclination angle of the shield jack
it can.

According to a third aspect of the present invention, there is provided a ball type shield excavator according to the first or second aspect , wherein the excavator, the erector, and the plurality of shield jacks are accommodated in a spherical surface including the hemispherical surface. It was done. Therefore, as described in claim 1 , by rotating the excavator about the center of the hemisphere as a rotation center in a state where the rear trunk portion is disconnected, the excavator is in a direction other than the excavated direction. To a desired direction, and dig into the desired direction. As <br/> other, performing an operation similar to that 請 Motomeko 1 or 2.

According to a fourth aspect of the present invention, in the ball-type shield excavator according to the third aspect of the present invention, the excavator is turned around a center of the hemispherical surface as a center of rotation so that the excavator is directed in a desired direction and the excavation direction is changed. It is configured to be changeable in the desired direction.

Therefore, as described in the third aspect, the excavator is rotated about the center of the hemispherical surface in a state where the rear trunk portion is disconnected, so that the excavator can be moved to a desired position. Direction, the digging direction can be changed to the desired direction and digging can be performed. Other, Sosu the effect similar to that of 請 Motomeko 3
You.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. The ball-type shield excavator according to the present embodiment is an excavator for excavating a tunnel-shaped underground passage (underground passage such as water supply, sewer, common ditch, underground passage, subway) having an excavation diameter of about 2 to 15 mφ. FIG.
As shown in FIG. 3, this ball type shield machine 1
Is an excavator 2 and, for example, 20 sets of shield jacks 3
And a cylindrical rear body 4 connected to the rear end of the excavator 2 by bolts (this is a tail plate 4a and a cylindrical seal plate 4b connected to the rear end of the tail plate 4a).
And an erector 6 for constructing a lining segment. The ball type shield machine 1
Among them, components other than the rear trunk portion 4 are configured so as to be accommodated in a spherical surface K having a diameter substantially equal to the excavation diameter and centered on the center A. Therefore, it is called a ball type shield machine.

First, the excavator 2 will be described. The excavator 2 includes a main body frame 10, a cutter frame 20 rotatably mounted on the main body frame 10, a plurality of cutter bits 30 mounted on the cutter frame 20, and, for example, seven electric motors 40 for driving the cutter frame 20 to rotate. (These correspond to cutter motors, but may be constituted by hydraulic motors), and have a muddy water discharge mechanism 50 for adding water to the excavated earth and sand and discharging fluidized muddy water.
The excavator 2 is configured so as to be substantially accommodated in a hemispherical surface S having a diameter equal to the excavation diameter and having a center A as a center and a narrow annular surface R connected to the hemispherical surface S in a stepped manner.

The main body frame 10 is a stationary frame that is not driven to rotate. The main body frame 10 includes a central support member 11, a rear end member 12 composed of a plurality of members extending from the central support member 11 to the outer peripheral side, and a rear end. An outer peripheral member 13 forming an outer peripheral portion of the side member 12, and a rear end side member 1 at a rear end;
The cylindrical member 14 has a cylindrical member 14, a front end wall member 15 (bulk head) located inside the front end of the cylindrical member 14, an annular tapered wall member 16 extending from the outer surface to the outer periphery of the cylindrical member 14, and the like. The front end wall member 15, the cylindrical member 14, and the annular tapered wall member 16 constitute a partition wall for blocking muddy water in the chamber 17 on the front end side. The annular tapered wall member 16
Is inside a predetermined length portion on the rear end side of the cutter frame 20.
A tape that extends along the vicinity and has a smaller diameter toward the front
It is formed in a pa shape.

The cutter frame 20 has a hemispherical structure along the inside of a hemisphere having a diameter substantially equal to the excavation diameter (diameter smaller than the excavation diameter by twice the protrusion allowance of the cutter 30) with the center A as a center. It is composed. The cutter frame 20 includes a central member 21, for example, six radial members 22 extending in a radial direction from the central member 21, an annular member 23, and an annular member 2 at a position between the radial members 22.
For example, six outer radial members 2 extending radially from 3
4. An annular member 25 at the outer peripheral portion, a cutter drum 26 which is a supporting annular member integrally extending rearward from the annular member 23.
Etc.

A plurality of cutter bits 30 are fixed to both surfaces of the radial member 22 and the outer radial member 24 of the cutter frame 20 at predetermined intervals by bolts or welding. Reference numeral 30a is located on a hemispherical surface S whose center is the center A and whose diameter is the excavation diameter.

The outer peripheral surface and the inner peripheral surface of the cutter drum 26 are sealed with sealing materials 27a and 27b, and a ring gear 28 having internal teeth is fixed to the rear end surface of the cutter drum 26. An annular bearing support 29b and the bearing support 29b are supported by the cylindrical member 14 via a fixed web 29c. The seven electric motors 40 are arranged in front and rear at circumferentially equal positions, and a pinion gear 41 fixed to an output shaft of each electric motor 40 is meshed with the ring gear 28. Therefore, when the seven electric motors 40 are driven to rotate in the forward or reverse direction, the cutter frame 20 is driven to rotate in the forward or reverse direction, and excavation over the entire surface of the hemisphere S is performed by a large number of cutter bits 30. .

To explain the muddy water discharging mechanism 50, a water supply pipe 51 for supplying pressurized water from a pressure supply pump (not shown) is provided along the vicinity of the axis.
2 is provided, and the front end of the water pipe 51 is open to the chamber 17. Discharge pipe 53 is provided for discharging the muddy water chamber 17, the discharge pipe 53, valve 54 is interposed, the discharge pipe 54 extends towards later along the axial vicinity portion is connected to an external exhaust system ing. Water pipe 51 and discharge pipe 54
The portion behind the erector 6 is formed of a flexible hose. The earth and sand excavated by the large number of cutter bits 30 is mixed with water supplied from the water supply pipe 51 to be mixed and muddy, and is discharged from the discharge pipe 53 to the outside.

Next, the shield jack 3 will be described. Twenty sets of the shield jacks 3 are disposed between the cylindrical member 14 and the annular tapered wall member 16 and at equally spaced positions around the circumference of the space on the rear side . The shield jacks 3 are double-acting hydraulic cylinders for generating a thrust for excavation. Each shield jack 3 is connected to a hydraulic supply unit (not shown) via a hydraulic hose, and can drive each shield jack 3 independently. It is configured in.

Each shield jack 3 has an annular tapered wall portion.
Sloping posture near the inside of the material 16 and the space behind it
Disposed, each shield jack 3 is swingably mounted via a pin coupling portion 60 and a trunnion support portion 61,
The front end of the jack body of each shield jack 3 is pinned
The annular tapered wall member 16 of the partition wall by the joint 60
Connected to the part near the front end of the vehicle so that the inclination angle of the inclination posture can be changed
Have been. An axially slidable shoe member 62 is connected to the tip end of the rod of each shield jack 3 on the inner surface of the tail plate 4a by a ball joint. The shield jack 3 extends the rod, and the shoe member 62
The excavation thrust is generated by kicking the front end of the existing segment 64 through. A swing hydraulic cylinder 63 that swings and drives each shield jack 3 is arranged in the radial direction and fixed to the cylindrical member 14, and its rod supports the shield jack 3 via a trunnion support 61.

Next, the rear body 4 will be described. The tail plate 4a is a cylindrical body having a diameter slightly smaller than the excavation diameter, and has a predetermined length in the axial direction. The front end of the tail plate 4 a
No. 0 is connected to the outer peripheral member 13 by bolts and nuts so that the connection can be released. The tail plate 4a serves as a basis for segment construction by constructing a segment on the inner surface thereof, and at the same time, cooperates with the seal plate 4b to shut off water flowing from the excavated surface. The seal plate 4b is a cylindrical body having the same diameter as the tail plate 4a, is fixed to the rear end of the tail plate 4a, and has a plurality of inner surfaces of the seal plate 4b for contacting the outer surface of the segment 64 to block water. Is mounted.

Next, the erector 6 for constructing the segment 64 will be described briefly since it is a general one. The erector 6 is supported by a cylindrical member 11a of the central support member 11 via a bearing so as to be rotatable via a bearing, a guide cylinder 66, and a guide that is guided by the guide cylinder 66 and is movable in the radial direction. The rod 67, the erector body 68 attached to the tip of the guide rod 67, and the erector body 6
A hydraulic cylinder 69 that drives the actuator 8 upward and downward in the radial direction, a hydraulic or electric drive motor (not shown) that rotationally drives the support 65, and the like are provided.

Next, the operation of the ball-type shield machine 1 described above will be described with reference to FIGS. As shown in FIG. 4, the excavator 2 is operated to excavate the underground passage while lining the excavated inner surface of the underground passage with the segment 64 by the erector 6. The operation in this case is similar to that of a normal excavator.

Here, when the excavation direction is changed to a desired second direction different from the first direction at the end of the first direction underground passage which has been excavated straight in a predetermined first direction. 5. As shown in FIG. 5, the rear body 4 is disconnected and the digging is continued, and as shown in FIG. 75
Are arranged in a ring shape and the front end of the block 75 is kicked by the rods of the 20 sets of shield jacks 3 so that the rear end of the spherical surface K is located a predetermined distance ahead of the front end of the rear trunk 4 as shown in FIG. Dig and move forward until it comes.

A number of nozzles are previously inserted many times from the ground via boring into the entire area of the terminal end part for which the direction is changed, and a ground improvement agent for waterproofing is injected from the nozzles to harden the ground. Stop water treatment. The cross-hatched area in the figure is the area where the water stop processing has been performed. However, excavator 2
In addition, an injection mechanism including a nozzle and a piping system for injecting the ground improvement agent may be installed in advance, and the injection mechanism may perform the water stopping process. Next, as an example of the case where the direction is changed 90 degrees horizontally to the left, the rotation of the cutter frame 20 of the excavator 2 is stopped, and for example, eight sets of shield jacks 3 located in the right half part are used. In the following manner, the portion of the ball-type shield excavator 1 excluding the rear trunk 4 (this is referred to as the shield excavator main body) is rotated in a desired direction about the center A as a rotation center. Point the shield machine in the desired direction.

In this case, the block 75 in the left half is removed, and the blocks 75 in eight rows corresponding to the eight sets of shield jacks 3 in the right half are kept in contact with the front ends of the existing segments 64, and the blocks 75 are removed. Fix it to the excavation wall with temporary anchor bolts. Each of the eight rows of blocks 75 is kicked by the shoe members 62 of the eight shield jacks 3 to rotate the shield machine body by a predetermined angle.
The row blocks 75 are additionally provided and fixed, and the shield machine is repeatedly rotated by a predetermined angle (see FIGS. 8 and 9). The blocks 75 in each row may have an independent structure for each shield jack 3 or a structure in which a plurality of shield jacks 3 are connected.

Next, as shown in FIG. 10, at the time when the direction change of the shield machine in the second direction, which is 90 degrees leftward with respect to the first direction, is completed, the rear trunk 4 At the position of the front end, a bank 76 composed of a semi-circular plate that covers the left half of the excavation pit is arranged transversely, and earth and sand 77 are buried in the front side of the bank 76. Then, to start the excavation toward the second direction from the state shown in FIG. 10, in the time of the predetermined small distance excavation, to abut against the contact and the right end of Tsutsumiita 76 to the left edge of the block 75 of eight columns Then, a divided ring member 78 for supporting the reaction force is assembled and fixed in a ring shape.

Next, the ring member 78 is excavated for a predetermined distance by kicking the ring member 78 with the 20 sets of shield jacks 3, and thereafter, an excavating block (not shown) corresponding to the 20 sets of shield jacks 3, similar to the block 75. While supporting the reaction force via the excavation block, remove the excavation block at the position where the excavation has proceeded by a distance approximately equal to the diameter of the excavation pit,
As shown in FIG. 11, a rear body 4A composed of an assembling tail plate 4c and a seal plate 4d which can be disassembled separately from the tail plate 4a and the seal plate 4b is assembled and set. The inner surface is covered with, for example, three rings of segments 64, and then digged in the second direction in the same manner as the digging in the first direction, and lining with the segments 64 via the erector 6.

In the above-described ball-type shield excavator 1, the cutter frame 20 is formed in a hemispherical structure along the inside of a hemispherical surface having a diameter substantially equal to the excavation diameter. The shield excavator is configured to be located on the hemispherical surface S having the same diameter as the excavation diameter, and furthermore, the shield machine is configured to be housed in the spherical surface including the hemispherical surface S, so that the following effects are obtained. As described above, with the center A of the hemisphere S as the center of rotation,
The direction of excavation can be changed to a desired direction, and the direction can be changed at a gentle or steep angle.

In the above example, a 90-degree direction change from a horizontal underground passage to a horizontal underground passage has been described as an example, but a 90-degree or desired direction change from a vertical underground passage to a horizontal underground passage, and vice versa. 90 from horizontal underground passage to vertical underground passage
A directional change is possible, such as a degree or desired direction change, a 90 degree or horizontal desired turn from a horizontal underground passage to a horizontal underground passage. Furthermore, even if the excavation direction is changed, the excavation diameter does not change, and the direction can be changed any number of times. Furthermore, since the cutter frame 20 is configured in a hemispherical structure, a plurality of cutter bits 30 are mounted on the cutter frame 20, and the shield machine is configured to be able to be housed in a spherical surface.
It is also advantageous in terms of manufacturing cost.

The above embodiment can be partially modified as follows. 1) Although the operation of the excavator 2 is stopped during the excavation direction change, the direction change may be performed while the cutter frame 20 of the excavator 2 is rotated at a low speed in order to reduce the resistance during the direction change.
In this case, the muddy water discharge mechanism 50 may be operated or may be stopped. 2] A block 7 for supporting a reaction force when changing the excavation direction.
5, the direction may be changed while the direction of the shield jack 3 is regulated by the hydraulic cylinder 63 and the excavation wall surface is kicked by the shoe member 62 at the tip of the rod of the shield jack 3.

3) During the excavation direction change, the left half of the shield excavator body may be pulled backward by a winch or the like in parallel with the operation of the shield jack 3 on the right half. 4) Instead of the muddy water discharge mechanism 50, a sediment discharge mechanism that discharges sediment using a belt conveyor or the like may be provided.

[0037]

According to the ball type shield excavator of the first aspect, a plurality of cutter bits of the excavator are mounted.
Cutter frame has a hemisphere with a diameter approximately equal to the drilling diameter
The rear body is configured to be substantially hemispherical along the inside of the surface, and the rear trunk is releasably connected to a rear end of the excavator. Therefore, when changing the excavation direction, the excavator is turned in a desired direction by rotating the excavator about the center of the hemisphere as a rotation center in a state where the rear trunk portion is disconnected. The digging direction can be changed to the desired direction.

Therefore, the direction of excavation can be changed to a gentle angle or a steep angle, can be changed to a desired direction, and even if the direction is changed, the excavation diameter remains unchanged, and the direction can be changed at a desired position during excavation. Direction can be changed several times. Moreover, if the associated equipment such as an erector and a shield jack is arranged so as to be accommodated in the spherical surface including the hemisphere, the excavator can be rotated about the center of the hemisphere as a rotation center. The structure is not so complicated. Connect each shield jack to the rear end of the cutter frame.
Extends along the inside of the predetermined length and decreases in diameter toward the front
Inclined near and inside the annular tapered wall member
Lengthen each shield jack,
The stroke can be increased.

In the ball-type shield machine according to claim 2, the jack body of each of the shield jacks is connected to a tranny.
Oscillating hydraulic cylinder capable of oscillating drive via ON support
The excavator is provided by multiple shield jacks.
The tilt angle of each shield jack changes when moving forward
However, swing each shield jack with the swing hydraulic cylinder.
Dynamic driving changes the tilt angle of the shield jack.
Can be made.

In the ball type shield excavator according to the third aspect , the same effect as in the first or second aspect is obtained, but the excavator, the erector, and the plurality of shield jacks are provided within a spherical surface including the hemispherical surface. It is configured to be storable. Therefore, as described in claim 1 , by rotating the excavator about the center of the hemisphere as a rotation center in a state where the rear trunk portion is disconnected, the excavator is in a direction other than the excavated direction. To a desired direction, and dig into the desired direction .

The ball-type shield excavator according to the fourth aspect has the same effect as that of the third aspect, except that the excavator is rotated about the center of the hemisphere as a rotation center to move the excavator in a desired direction. And the excavation direction can be changed to the desired direction. Therefore, as described in claim 3, the excavator is turned in a desired direction by rotating the excavator around the center of the hemispherical surface in a state where the connection of the rear trunk portion is released. The digging direction can be changed to the desired direction .

[Brief description of the drawings]

FIG. 1 is a sectional view of a ball-type shield machine according to an embodiment of the present invention.

FIG. 2 is a schematic front view of the shield machine shown in FIG. 1;

FIG. 3 is a rear view of a main part of the shield machine shown in FIG. 1;

FIG. 4 is an explanatory diagram of an operation during excavation in a first direction.

FIG. 5 is an operation explanatory view of a state in which the rear trunk portion is disconnected during excavation in the first direction.

FIG. 6 is an explanatory diagram of an operation during excavation in a first direction.

FIG. 7 is an operation explanatory diagram of a state immediately before a direction change from the first direction to the second direction.

FIG. 8 is an operation explanatory diagram of a state in which a direction change is started in a second direction.

FIG. 9 is an operation explanatory diagram showing a state during a direction change.

FIG. 10 is an operation explanatory diagram showing a state in which the direction change is completed.

FIG. 11 is an operation explanatory view showing a state in which excavation is being performed in a second direction.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 ball type shield machine 2 machine 3 shield jack 4 rear trunk 6 erector 10 main body frame 14 cylindrical member 15 front end wall member 16 annular tapered wall member 20 cutter frame 60 pin connecting portion 61 trunnion support portion 63 hydraulic cylinder for swinging

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int.Cl. ⁶ , DB name) E21D 9/06 301 E21D 9/06 302

Claims (4)

(57) [Claims] An excavator for excavating a tunnel-shaped underground passage.
And a cylindrical rear trunk connected to the rear end of the machine
, Erector, and multiple shields for generating excavation thrust
A shield machine having a jack and a plurality of cutter bits for the machine
The frame is inside a hemisphere with a diameter approximately equal to the drilling diameter
And a partition wall for partitioning the chamber of the excavator is provided with a cutter.
Extends near the inside of the specified length on the rear end of the frame
Annular tapered wall member with a smaller diameter toward the front
A shield wall member, and each of the shield jacks is provided with an inner side of an annular tapered wall member.
It is installed in an inclined posture over the space near and behind it, and
The front end of the jack body is a partition wall.
The inclined posture is provided at a position near the front end of the annular tapered wall member.
The rear trunk portion is releasably connected to the rear end of the excavator.
A ball-type shield excavator characterized by the following. 2. A jack body of each of said shield jacks.
Oscillation hydraulic pressure that can be oscillated through the trunnion support
The bob according to claim 1, further comprising a cylinder.
Type shield machine. And wherein the excavator, erector and, a plurality of shield jacks, ball shield according to claim 1 or 2, characterized in capable of accommodating that configured in the sphere including the hemispherical surface Excavator. 4. The excavator is turned around a center of the hemispherical surface as a center of rotation so that the excavator is directed to a desired direction, and the excavation direction can be changed to the desired direction. Item 4. A ball-type shield excavator according to item 3 .