JPH10246090A - Shaft excavator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to efficiently conveying excavated earth and sand from the inside of a shaft in the case the shaft is excavated. SOLUTION: A screw conveyer 12 for conveying excavated earth and sand and a plurality of driving devices 7 for driving an excavator 1 are provided in the inside of a shield handle 8 for preventing collapse of a bedrock, the excavator 1 is connected to driving shafts 6 of the driving devices 7 and is eccentrically moved from the shaft centers of the driving shafts 6, and pivot sections 5 are arranged at equal intervals. Bearing members 2 and 3 connected respectively to the pivot sections 5 and excavation bits 4 loaded to the bearing members 2 and 3 to excavate earth and sand are included, distance between the pivot sections adjacent to each other of them is so set that it is equal to distance between the shaft centers of the driving shafts 6 corresponding to the pivot sections, a main earth and sand collection inlet 13 is provided to the approximately center of a square formed by connecting the shaft centers of the driving shafts 6, and a stirring wing 14 making earth and sand flow is extended in the direction of the diameter of the driving shafts 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
Shaft excavator capable of excavating a vertical hole having a large diameter, that is, a shaft.

[0002]

2. Description of the Related Art As an excavator for excavating a horizontal hole having a large diameter of about 10 m in the ground, there is a shield excavator for excavating a horizontal hole forming a tunnel. FIG. 10 is a longitudinal sectional view showing an example of a conventional shield machine used for excavation of such a horizontal hole, and FIG. 11 is a front view showing an excavating tool part corresponding to the view taken along the line EE in FIG. It is.

The conventional shield machine shown in FIGS. 10 and 11 has an excavation tool 50 for excavating the ground at a front portion. The excavator 50 is connected to a driving device 52 having a driving shaft 51. A shield hull 53 forming an outer shell is provided so as to surround the driving device 52. The shield hull 53 prevents the excavated earth and sand from collapsing. Behind the driving device 52, a plurality of shield jacks 54 for propelling the excavating tool 50 and the driving device 52 by a predetermined distance are provided. At the rear portion of the shield jack 54, a segment 55 that is annularly arranged along the inner wall of a horizontal hole formed by excavation with the excavator 50 is assembled. The width dimension of this segment 55 is one of the drilling tools 50.
This corresponds to the number of propulsion distances, that is, the stroke of the shield jack 54. In addition, the collapse of the ground is prevented by the segment 55. Each of the segments 55 is adapted to be assembled by an erector 56.

A screw conveyor 57 for transporting the earth and sand excavated by the excavation tool 50 to a predetermined rear position.
Is provided. The screw conveyor 57 is entirely disposed in an inclined manner, and includes a casing and blades housed in the casing.

In this shield excavator, when the drive unit 52 is operated and the shield jack 54 is operated, the excavating tool 50 is propelled by the stroke of the shield jack 54 while rotating to excavate the ground. Is formed. The erector 56 extends along the inner wall of the lateral hole formed in this manner.
As a result, the segment 55 is assembled in an annular shape. Such an operation is repeatedly performed, and the distance is sufficiently long.
A large-diameter lateral hole having a diameter of, for example, about 10 m, that is, a tunnel is formed.

During the above-described excavation operation, the earth and sand generated by the excavation falls near the lower part of the excavator 50 by its own weight. When the screw conveyor 57 is driven, the blades rotate, and the earth and sand located near the lower part of the excavating tool 50 is taken in from the earth and sand inlet 60 of the screw conveyor 57, and is carried on the blades to a predetermined rear position.

[0007]

The prior art described above is
Since it is a shield propulsion machine that excavates a horizontal hole, it is effective for excavating a horizontal hole in the ground, but cannot be applied immediately to excavation of a shaft.

For example, in the case of excavation of the above-mentioned lateral hole,
Since the excavated earth and sand falls below the excavation tool 50 by its own weight, the screw conveyor 57 may be arranged so that the earth and sand intake port is located at one place below the excavation tool 50. However, in the case of excavation of a shaft, earth and sand generated by the excavation are distributed to each part in one horizontal plane. Therefore, if the screw conveyor is arranged so that the sediment intake port is located only at one location on the periphery of the excavated hole, the excavated soil cannot be efficiently conveyed, and a desired shaft cannot be formed. There is.

As described above, the conventional shield machine is effective in excavating a horizontal hole, but when it is applied to excavation of a vertical hole as it is, a problem arises in carrying out excavated earth and sand from the inside of the vertical shaft. Was something. Therefore, there has been a demand for a device capable of excavating a shaft having a large diameter, taking into consideration the removal of earth and sand.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned situation in the prior art, and has as its object to provide a shaft excavator capable of properly carrying excavated earth and sand out of the shaft when excavating the shaft. It is in.

[0011]

In order to achieve the above-mentioned object, the invention according to claim 1 of the present invention provides a digging tool for digging a shaft in the ground, and a plurality of driving devices for driving the digging tool. A shield hull that forms an outer shell and prevents the collapse of the ground, and a screw conveyor that conveys earth and sand excavated by the excavation tool, wherein the excavation tool is mounted on each drive shaft of the plurality of drive devices. Connected, eccentric from the axis of these drive shafts, and provided at equal distances from each other, a support member connected to each of these support portions, and mounted on the support member to excavate earth and sand. And the distance between adjacent shaft supports of the shaft supports is set to be equal to the distance between the shaft centers of the corresponding drive shafts, respectively, and each of the drive shafts Connect your heart The main and earth intake ports of the screw conveyor are arranged inside the polygon to be formed, and are integrally provided on each of these drive shafts along the radial direction of the drive shaft. The structure is provided with a stirring blade for flowing the sediment.

According to the first aspect of the present invention, by rotating each drive shaft of the drive device, each of the shaft support portions and each of the stirring blades are rotated. Since each of the shaft supports is provided at a predetermined equidistant distance from the axis of the drive shaft, the shaft supports rotate on the drive shaft with the equidistant radius of rotation. That is, each of the shaft supports performs a parallel crank motion. Thereby, the excavation bit can move in a region larger than the outer dimensions of the excavation tool via the support member connected to the shaft support portion, and excavate the ground. Also, during the excavation of the ground by the excavation bit, the earth and sand excavated by the stirring blades is taken into the main and sediment of a screw conveyor arranged inside a polygon formed by connecting the respective shaft centers of the drive shafts. It is pushed toward the mouth and collected. The sediment collected in this way is taken into the screw conveyor from the main / sediment intake port and transported to the ground. In this way, the excavated earth and sand can be discharged from the shaft. Also,
An excavator, a plurality of driving devices for driving the excavator, and a shield hull forming an outer shell and preventing collapse of the ground can form the basic structure of the shield excavator. When this shield excavator is applied, a shaft with a large diameter can be excavated.

[0013] In order to achieve the above object, the invention according to claim 2 of the present invention is directed to the invention according to claim 1, wherein the main / sediment intake port of the screw conveyor is connected to each of the drive shafts. The configuration is such that the polygon is formed substantially at the center of the polygon formed by connecting the axes.

According to the second aspect of the present invention, the main and earth and sand intakes of the screw conveyor are arranged at a position where the earth and sand can easily gather. That is, when the stirring blade rotates with the rotation of the drive shaft, the excavated earth and sand receives a force in a tangential direction of a circle drawn by the rotation of the stirring blade. As a result, the excavated earth and sand is extruded along the outer peripheral surface of the drive shaft. The main / sediment intake of the screw conveyor is located at the center of the portion where the rotation trajectories of the tips of the stirring blades are gathered, that is, at the position where the flow speed of the earth and sand is the slowest. As a result, a large amount of excavated sediment collects in the main / sediment intake port, and sediment can be efficiently taken into the screw conveyor from the main / sediment intake port.

According to a third aspect of the present invention, there is provided the invention as set forth in the second aspect, wherein the screw conveyor is formed by connecting the respective shaft centers of the drive shaft. With one side of the polygon having a side as a symmetry axis, a sub-soil intake port is provided at a symmetric position of the main / soil intake port.

In order to achieve the above object, the invention according to claim 4 of the present invention is directed to the invention according to claim 1 or 2, wherein the screw conveyor connects the respective shaft centers of the drive shaft. With one side of the formed polygon as the axis of symmetry, there is a configuration in which a secondary / soil intake port is provided closer to the shield hull than a symmetric position of the main / soil intake port.

According to the third and fourth aspects of the present invention, in particular, a shield for forming another part where the excavated earth and sand tends to gather due to a reduced flow speed of the excavated earth and sand pushed by the rotation of the stirring blade. Since the auxiliary / sediment intake port of the screw conveyor is provided near the hull, the excavated earth and sand can be more efficiently taken into the screw conveyor.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a shaft excavator according to the present invention will be described below with reference to the drawings. FIG. 1 is a longitudinal sectional view showing a first embodiment of a shaft excavator according to the first and second aspects of the present invention, FIG. 2 is a rear view corresponding to an arrow AA in FIG. 1, and FIG. FIG. 2 is an enlarged view corresponding to the view taken along arrow BB of FIG.

The basic structure of the first embodiment except for the excavator 1 and the screw conveyor 12 is the same as that of a shield machine used for excavating a horizontal hole. That is, even in the first embodiment, as shown in FIG. 1, a plurality of driving devices 7 including, for example, hydraulic motors, and a predetermined plurality of driving devices 7 among these driving devices 7 drive. And a drive shaft 6. For example, four drive shafts 6 are provided, and are arranged such that a square is formed when the shaft centers are connected. So as to surround each of the driving devices 7,
A shield hull 8 forming an outer shell is provided. The shield hull 8 is formed, for example, in a cylindrical shape, and prevents collapse of excavated earth and sand. Behind the drive 7
A plurality of shield jacks 9 are provided to propel the excavating tool 1 described below and the driving device 7 described above for a predetermined distance.
At the rear part of the shield jack 9, a segment 10 that is annularly arranged along the inner wall of the shaft formed by excavation of the ground is assembled. The width of the segment 10 corresponds to, for example, the stroke of the shield jack 9. Further, the collapse of the ground is prevented by the segment 10. Each of the segments 10 is adapted to be assembled by an erector 11.

As shown in FIG. 1, a partition wall 8a for preventing excavated earth and sand from entering the inside of the shield hull 8 is provided at a lower end portion of the shield hull 8. Each of the large diameter portions formed at the lower end of the drive shaft 6 described above is
It protrudes below a.

An excavator 1 for excavating a shaft in the ground has the following configuration, for example. That is, as shown in FIG.
A shaft support 5 connected to each of the large-diameter portions of the four drive shafts 6 and eccentric from the axis of the drive shaft 6 and provided at an equal distance from each other;
Girder-shaped support member 2 connected to each of the shaft supports 5
And an annular support member 3 fixed to the girder support member 2, and a girder support member 2 and an annular support member 3
And a drill bit 4 attached to each of them.
As illustrated in FIG. 3, only one set is illustrated, so that the distance SA between the adjacent shaft supports 5 of the respective shaft supports 5 is equal to the distance SB between the axes of the corresponding drive shafts 6. Is set to

Screw conveyor 1 for transporting excavated earth and sand
As shown in FIG. 1, 2 is disposed at a central position substantially coinciding with the central axis of the shield hull 8 and along the vertical direction, and is formed near the lower end of the screw conveyor 12 to remove excavated earth and sand. The main / soil inlet 13 to be taken into the screw conveyor 12 is disposed inside the above-described square formed by connecting the axis of the drive shaft 6, for example, at a substantially central position of the square.

As shown in FIGS. 2 and 3, the drive shaft 6 is integrally formed with each of the drive shafts 6 so as to extend along the radial direction of the drive shaft 6, for example, with each of the shaft support portions 5 connected to the drive shaft 6. And a stirring blade 14 for flowing earth and sand excavated by the above-described excavation tool 1
It has.

In the first embodiment configured as described above,
When each of the driving devices 7 is driven while the shield jack 9 is driven, each of the four driving shafts 6 rotates, and accordingly, each of the four shaft supports 5 and the stirring blades 14 rotates the driving shaft 6. Rotate around the axis. Since each of the four shaft support portions 5 is provided at a predetermined equal distance from the axis of the drive shaft 6, the four shaft support portions 5 rotate on the drive shaft 6 with the equal distance as a rotation radius. That is, these four
The parallel crank motion can be performed by the two shaft supports 5. As a result, the drill bit 4 is connected via the girder-shaped support member 2 connected to the shaft support 5 and the annular support member 3.
Moves downward in a region larger than the outer shape of the drilling tool 1 provided with the drill bit 4, that is, the outer shape of the annular support member 3, that is, in a large region corresponding to the outer diameter of the shield hull 8. Excavate the ground in the direction.

During the excavation of the ground by the excavation bit 4, each of the four stirring blades 14 rotates while drawing a circle as shown by a trajectory 14a shown by a two-dot chain line in FIG. The excavated sediment is pushed by the agitating blades 14 in the direction of the main / sediment intake 13 disposed inside a square formed by connecting the respective axes of the drive shafts 6 and collected. That is, the stirring blade 1 is rotated with the rotation of the drive shaft 6.
When the 4 rotates, the excavated earth and sand is pushed out along the outer peripheral surface of the drive shaft 6. In particular, in the first embodiment, the main / sediment intake 13 is located at a position where the excavated sediment easily gathers. The main / sediment intake 13 is a center of a square formed by connecting the respective axes of the drive shaft 6,
In other words, it is located at the center of the portion where the rotation trajectories of the tip of the stirring blade 14 gather. This central position is the position where the flow speed of the excavated earth and sand is the slowest. As a result, a large amount of earth and sand is collected in the main and earth and sand intake 13, and the earth and sand can be efficiently taken into the screw conveyor 12 from the earth and sand intake 13. The excavated earth and sand taken into the screw conveyor 12 is transported to the ground by rotation of the blades.

The driving device 7 having the driving shaft 6, the shield hull 8, the partition 8a, the shield jack 9,
The segment 10, the erector 11, and the like form a basic structure of a shield machine used for excavation of a horizontal hole forming a tunnel. Therefore, the shield machine can be applied. Then, it is possible to excavate a large-diameter shaft having a sufficiently large diameter.

According to the first embodiment configured as described above, when excavating a shaft, excavated earth and sand can be favorably carried out of the shaft, whereby a large-diameter shaft can be formed.

FIG. 4 is a longitudinal sectional view showing a second embodiment corresponding to claims 1, 2 and 3 of the present invention, and FIG.
It is a rear view corresponding to an arrow.

In the second embodiment shown in FIGS. 4 and 5, similarly to the first embodiment, the screw conveyor 12 for transporting excavated earth and sand is provided with a center that substantially coincides with the central axis of the shield hull 8. Position, and along the vertical direction, and a main / sediment intake port 13a for taking excavated earth and sand into the screw conveyor is provided inside a square formed by connecting the axis of the drive shaft 6, for example, It is arranged at a substantially central position of the square, and is excavated on the screw conveyor 12 at a symmetric position of the main and earth and sand intake ports 13a with one side of the square formed by connecting the axis of the drive shaft 6 as a symmetry axis. A sub / soil intake 13b for taking in earth and sand is arranged. Other configurations including the excavator 1 are configured, for example, in the same manner as in the first embodiment described above.

In the second embodiment configured as described above,
In addition to obtaining the same operation and effect as the above-described first embodiment, in particular, the flow rate of the excavated sediment pushed along with the rotation of the stirring blade 14 is reduced, and other parts where these excavated earth and sand are likely to gather are removed. The auxiliary / sediment intake 13b of the screw conveyor 12 is also provided in the vicinity of the shield hull to be formed. Can be carried out of the shaft.

FIG. 6 is a longitudinal sectional view showing a third embodiment according to claims 1 and 2 of the present invention, and FIG. 7 is a transverse sectional view taken along the line DD of FIG.

In the third embodiment, the form of the stirring blade 15 is different from that of the first embodiment shown in FIGS. Other configurations are, for example, the same as those in the first embodiment.

Each of the stirring blades 15 includes an overhang plate 15 a integrally fixed to the shaft support 5 connected to the drive shaft 6,
A plurality of rods 15b fixed to the overhang plate 15a and arranged along the radial direction of the drive shaft 6, and another rod 1 fixed on the drive shaft 6 and arranged in a line with the rod 15b described above.
It consists of six.

In the third embodiment having the above-described structure, when the drive shaft 6 is rotated, the rod 16 is rotated, and the shaft support 5 is rotated.
a and the rod 15b rotate, and the side portions of the rods 16 and 15b,
The excavated earth and sand is extruded by the side of the overhang plate 15a, and the excavated earth and sand can be collected in the direction of the main / soil intake 13 located at the center of a square formed by connecting the axis of the drive shaft 6. Similarly to the first embodiment described above, excavated earth and sand can be efficiently taken into the screw conveyor 12 from the main / soil intake port 13, and the same operation and effect as those of the first embodiment can be obtained.

FIG. 8 is a rear view showing a digging tool portion constituting a fourth embodiment corresponding to claims 1, 2 and 3 of the present invention.

In the fourth embodiment, the shield hull 17
Is formed by rounding each of the corners of the equilateral triangle. Three drive shafts 21 of a drive device (not shown) housed in the shield hull 17 are provided, and these drive shafts 21 are arranged so that connecting the axes of the drive shafts 21 forms an equilateral triangle. It is. The excavator 18 is formed so as to correspond to the shape of the shield hull 17. That is,
Each of the large-diameter portions of the three drive shafts 21 is provided with a shaft support portion 20 eccentric from the axis of the drive shaft 21 and equidistant from each other, and is connected to each of these three shaft support portions 20. An annular support member 19 is provided, and a not-shown excavation bit attached to the annular support member 19 is provided. The above-mentioned annular support member 19 is a shield hull 1
Although it is formed sufficiently smaller than the outer shell size of 7,
Like the shield hull 17, the shape is a shape in which each corner of the equilateral triangle is rounded. Also, the shaft support 20
Are set so that the distance between the adjacent shaft supports 20 is equal to the distance between the shaft centers of the corresponding drive shafts 20, respectively.

The main / soil inlet 22 for taking excavated earth and sand into a screw conveyor (not shown) is located inside the above-described equilateral triangle formed by connecting the axes of the drive shafts 21, for example, substantially at the center of the equilateral triangle. It is located in. Further, with one side of an equilateral triangle formed by connecting the axis of the drive shaft 21 as a symmetry axis, a sub-soil intake port for taking in excavated earth and sand into a screw conveyor (not shown) at a symmetric position of the main and earth / sand intake ports 22. 23 are arranged respectively. Further, each of the drive shafts 21 is integrally formed with each of the drive shafts 21 so as to extend along the radial direction of the drive shaft 21, for example.
A stirrer 24 for flowing earth and sand excavated by the above-described excavation tool 18 is formed integrally with each of the shaft supports 20 connected to the excavator 18 so as to form a cross shape similar to that described in the first embodiment. It has.

In FIG. 8, reference numeral 17a denotes a partition. Although not shown, a shield jack, a segment, an elector, and the like equivalent to those of the first embodiment are also provided.

In the fourth embodiment having the above-described structure, similarly to the first embodiment, when the unillustrated shield jack is driven and each of the driving devices is driven, three driving shafts are required. Each of the rotations 21 rotates, and accordingly, each of the three shaft supports 20 and the stirring blades 24 rotates about the axis of the drive shaft 21. 3
Each of the shaft supports 20 performs a parallel crank motion. As a result, the drill bit not shown in the drawing via the annular support member 19 connected to the shaft support portion 20 has a larger area than the outer shape of the annular support member 19, that is, a large area corresponding to the outer shell size of the shield hull 17. Go inside and excavate the ground in the downward direction.

Further, during the excavation of the ground by the excavation bit, excavated earth and sand is arranged at the center of an equilateral triangle formed by connecting the respective axes of the drive shafts 21 by the three stirring blades 24 respectively. It is pushed and collected in the direction of the main / sediment intake port 22, and is pushed and collected in the direction of the sub / sediment intake port 23 located near the shield hull 17. Therefore, these main and sediment intake ports 2
2. The earth and sand can be efficiently taken into the screw conveyor 12 from the auxiliary / sand intake port 23.

Further, similarly to the first embodiment, the drive shaft 2
1, a drive unit (not shown), a shield hull 17, a partition 17a, a shield jack (not shown), a segment,
Since the erector and the like form the basic structure of a shield machine used for excavating a horizontal hole forming a tunnel, a shield machine can be applied. Shafts of sufficiently large dimensions can be excavated.

FIG. 9 is a rear view showing a digging tool portion constituting a fifth embodiment corresponding to claims 1, 2 and 4 of the present invention.

In the fifth embodiment, the shield hull 25
Is a shape obtained by rounding each of the corners of the inequality triangle. Three drive shafts 29 of a drive device (not shown) housed in the shield hull 25 are provided in the same manner as in the fourth embodiment described above. These drive shafts 29 are arranged such that The excavator 26 is a shield hull 2
5 is formed corresponding to the shape of FIG. That is, each of the large-diameter portions of the three drive shafts 29 is eccentric from the axis of the drive shaft 29 and is furthermore equidistant from each other.
And an annular support member 27 connected to each of the three shaft support portions 28;
And a not-shown excavation bit to be attached to the vehicle. Although the above-mentioned annular support member 27 is formed sufficiently smaller than the outer shell size of the shield hull 25, its shape is similar to that of the shield hull 25, and each of the corners of the unequal triangle is rounded. Shape. Further, the distance between the adjacent shaft supports 28 of the shaft supports 28 is set to be equal to the distance between the shaft centers of the corresponding drive shafts 29, respectively.

The main / soil intake port 30 for taking excavated earth and sand into a screw conveyor (not shown) is disposed inside the above-described unequal triangle formed by connecting the axis of the drive shaft 29. Further, a screw (not shown) is located closer to the shield hull 25 than the symmetrical position of the main and sediment intake ports 30 when one side of a scalene triangle formed by connecting the axes of the drive shafts 29 is a symmetric axis. A sub / soil intake port 31 for taking excavated earth and sand into the conveyor is arranged. In addition, as described in the first embodiment, the drive shaft 29 is integrally formed with each of the drive shafts 29 so as to extend along the radial direction of the drive shaft 29, for example, each of the shaft supports 28 connected to the drive shaft 29. A similar vertical section is formed in a cross shape, and is provided with a stirring blade 32 for flowing earth and sand excavated by the excavating tool 26 described above.

In FIG. 9, reference numeral 25a denotes a partition. Although not shown, a shield jack, a segment, an elector, and the like equivalent to those of the first embodiment are also provided. In this way, the outer shell shape of the shield hull 25 and the entire shape of the excavation tool 26 are formed as unequal triangles.
In the fourth embodiment, the driving device is driven together with a shield jack (not shown) to rotate the drive shaft 29, thereby causing the shaft support portion 28 to perform a parallel crank motion. 26 moves in an area larger than the outer shape of the annular support member 27, that is, in a large area corresponding to the outer shell size of the shield hull 25,
Excavate the ground downward.

The excavated sediment is pushed and collected by the three stirring blades 32 in the direction of the main / sediment intake port 22 and the auxiliary / sediment intake port 31, and the excavated sediment is efficiently put into the screw conveyor 12. Can be captured.

Further, similarly to the first embodiment, the drive shaft 2
9, a drive unit (not shown), a shield hull 25, a partition 25a, a shield jack (not shown), a segment,
Since the erector and the like form the basic structure of the shield machine, the shield machine can be applied.
If this shield machine is applied, a shaft with a sufficiently large diameter can be excavated.

In each of the above embodiments, the ground is excavated downward to form a shaft, but it is also possible to excavate the ground upward to form a shaft.

[0049]

According to the above construction, the invention according to claims 1 to 4 of the present invention enables excavated earth and sand to be successfully carried out of the shaft by the screw conveyor when excavating the shaft. Thus, shaft excavation, which has been conventionally required, can be realized. In addition, the basic structure of the shield machine can be applied, and by applying the basic structure of the shield machine as described above, a large-diameter shaft can be excavated with high accuracy.

In the invention according to claim 2, the main
The sediment intake is arranged at a position where a large amount of excavated sediment is likely to collect. Therefore, excavated sediment can be efficiently taken into the screw conveyor from the main / sediment intake, thereby contributing to an improvement in the efficiency of sediment discharge work.

Further, in particular, in the invention according to claims 3 and 4,
In addition to taking in excavated sediment from the main and sediment intakes, it is also possible to take in excavated sediment collected near the shield hull from the secondary and sediment intakes, so that excavated sediment is more efficiently taken into the screw conveyor. It is possible to further improve the efficiency of the earth and sand discharge work.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first embodiment of a shaft excavator according to the present invention.

FIG. 2 is a rear view corresponding to an arrow AA in FIG. 1;

FIG. 3 is an enlarged view corresponding to the view taken along the line BB in FIG. 1;

FIG. 4 is a longitudinal sectional view showing a second embodiment of the present invention.

FIG. 5 is a rear view corresponding to the view taken along the line CC of FIG. 4;

FIG. 6 is a longitudinal sectional view showing a third embodiment of the present invention.

7 is a transverse sectional view corresponding to the view taken along the line DD in FIG. 6;

FIG. 8 is a rear view showing a digging tool part constituting a fourth embodiment of the present invention.

FIG. 9 is a rear view showing a digging tool portion constituting a fifth embodiment of the present invention.

FIG. 10 is a longitudinal sectional view showing an example of a conventional shield machine.

11 is a front view showing a digging tool portion corresponding to a view taken along the line EE in FIG. 10;

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 excavating tool 2 cross-girder support member 3 annular support member 4 drill bit 5 shaft support 6 drive shaft 7 drive device 8 shield hull 8 a partition wall 9 shield jack 10 segment 11 electrer 12 screw conveyor 13 main / sand intake 13a main / sand Intake port 13b Secondary / sediment intake port 14 Stirring blade 14a Trajectory 15 Stirring blade 15a Overhang plate 15b Rod 16 Rod 17 Shield hull 17a Partition wall 18 Drilling tool 19 Annular support member 20 Shaft support 21 Drive shaft 22 Main / sediment intake 23 Secondary / Sand intake port 24 Stirrer blade 25 Shield hull 25a Partition wall 26 Excavating tool 27 Annular support member 28 Shaft support 29 Drive shaft 30 Main / Sand intake port 31 Secondary / Sand intake port 32 Stirrer blade

 ──────────────────────────────────────────────────の Continuing on the front page (72) Inventor Kazunori Ueda 650 Kandamachi, Tsuchiura-shi, Ibaraki Hitachi Construction Machinery Co., Ltd. Tsuchiura factory

Claims (4)

[Claims] An excavator for excavating a shaft in the ground, a plurality of driving devices for driving the excavator, a shield hull forming an outer shell to prevent collapse of the ground, and excavation by the excavator A screw conveyor that conveys the soil and sand, wherein the excavator is connected to the respective drive shafts of the plurality of drive devices, the shafts are eccentric from the axes of the drive shafts, and are each provided at an equal distance from each other. A support portion, a support member connected to each of the support portions, and a drill bit mounted on the support member and excavating earth and sand, a distance between adjacent support portions of the support portions, The main and earth and sand intakes of the screw conveyor are set inside the polygon formed by connecting the respective axes of the drive shafts so as to be equal to the distance between the axes of the corresponding drive shafts. A shaft excavator, which is provided integrally with each of the drive shafts so as to extend along the radial direction of the drive shaft, and which is provided with stirring blades for flowing earth and sand excavated by the excavation tool. . 2. The shaft according to claim 1, wherein the main and earth intake ports of the screw conveyor are arranged substantially at the center of a polygon formed by connecting respective axes of the drive shafts. Excavator. 3. The screw conveyor has a sub / soil intake port at a symmetric position of the main / soil intake port with one side of the polygon formed by connecting the respective axes of the drive shafts as a symmetric axis. The shaft excavator according to claim 2, comprising: 4. The screw conveyor, wherein one side of the polygon formed by connecting the respective axes of the drive shafts is set as a symmetric axis, closer to the shield hull than a symmetrical position of the main / sediment intake port. The shaft excavator according to claim 1 or 2, wherein the shaft excavator has a sub / soil intake.