JPH03107095A - Shield drilling machine - Google Patents

Abstract

PURPOSE:To improve the take-in efficiency of sediment by forming a cutter head integrally with an inside skin plate of which cross section is formed in non-circular, and providing holes in the peripheral wall of the inside skin plate to arranged cutters having a small diameter. CONSTITUTION:The front face is drilled by a cutter 2 having a large diameter and cutters 4 having a small diameter, and the periphery of a tunnel is drilled by a fixed blade 11 to take the sediment into a mud pressure chamber 3 and a mud pressure chamber 5. Next, an elliptical inside skin plate 6 is rotated with the rotation of a cutter head 15 to stir the mud and the sediment while transporting the sediment sent to the mud pressure chamber 5 into the mud pressure chamber 3 through a side slit 7. Next, after drilling one segment, the mud including the sediment taken into the mud pressure chamber 3 is exhausted through a mud exhaust pipe 21. The efficiency can be thereby improved by stirring sufficiently.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention relates to a shield excavator used in the shield method of constructing tunnels, and in particular to a shield excavator used for forming tunnels with large cross sections and arbitrary cross sections. It's about machines.

``Conventional technology'' In recent years, for the purpose of constructing large-section tunnels such as railway tunnels in the ground in urban areas, a shield excavator with two cutters installed on the front side of a skin plate formed in both types has been used. Multi-face shield construction method for forming tunnels (see Japanese Patent Laid-Open No. 1988-1988) or a new shield construction method called double O-tube construction method (Japanese Patent Laid-Open No. 62-1988)
-47958) has been proposed and implemented.

However, the shield excavators applied to each of the above large-section shield construction methods have a basic structure in which two cutters are arranged in parallel in front of a skin plate with a cocoon-shaped cross section, so these shield excavators The disadvantages were that tunnel structures with cross-sectional structures such as , horseshoe shapes, and rectangles could not be constructed, and machine control such as direction control and correction was difficult.

Therefore, in order to solve the above-mentioned problems, the present applicant would like to first apply for a shield excavator that is easy to control and capable of excavating tunnels with large cross sections and arbitrary cross sections.
issue).

The shield excavator according to this application is shown in FIGS. 6 and 7.
As shown in the figure, the circular face excavated by the large-diameter cutter 2 supported by the rotating shaft l is stabilized by the mud pressure pumped into the mud pressure chamber 3, and the irregular-shaped face excavated by the small-diameter cutter 4 is stabilized by the mud pressure pumped into the mud pressure chamber 3. While the face is stabilized by mud water pressure and mud pressure, the face is excavated with each force I2.4, and the earth and sand in the mud pressure chamber 5 are removed by the mud water pressure by holes 7 provided in the peripheral wall of the inner skin plate 6. The mud is transferred into the chamber 3 and discharged to the outside together with the earth and sand in the mud pressure chamber 5. Therefore, the screw conveyor required in the conventional mud pressure shield method is no longer necessary, and a non-circular and large-section tunnel can be easily constructed by combining the circular part and the irregularly shaped part.

"Problems to be Solved by the Invention" However, in this shield excavator, as shown in FIG. Since the hole 7 is simply formed in the peripheral wall of the hole 6, there is a problem in reliably taking the earth and sand into the hole 7, and there remains room for improving the earth and sand taking efficiency.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a shield excavator that improves the efficiency of taking in earth and sand from a mud pressure chamber to a mud water pressure chamber.

"Means for Solving the Problems" In the present invention, the above problems are solved by using a shield excavator whose cylindrical inner skin plate has a non-circular cross-sectional shape. Here, the term "non-circular" refers to a shape other than a circle, such as an oval or an oval shape.

"Function" According to the shield excavator of the present invention, during tunnel excavation,
Since the cross-sectional shape of the inner skin plate is non-circular, the earth and sand excavated by a small-diameter cutter installed at the opening of the mud pressure chamber and sent into the mud pressure chamber are transported as the cutter head rotates. The mud is stirred inside the mud pressure chamber by the inner skin plate that rotates to form fluid soil. Also,
It is easily drawn into the holes formed in the peripheral wall and transported into the mud pressure chamber inside the inner skin plate.

"Embodiment" Hereinafter, an embodiment of the shield excavator of the present invention will be described with reference to FIGS. 1 to 4.

As shown in Figs. 1 and 2, this shield excavator excavates the ground using a large-diameter cutter 2 and a small-diameter cutter 4 provided at the front of a cylindrical outer skin plate 8 forming an outer shell. At the same time, the basic configuration is to excavate underground while assembling segments 9 (concrete segments, etc.) for the next excavation inside the outer skin plate 8.

The outer skin plate 8 has a substantially rectangular cross section, and has a partition wall 1 at the front thereof covering the tip opening.
0 is set. This partition part 10 consists of a fixed blade 11 provided along the inner peripheral surface of the outer skin plate 8 and a partition wall 12, and a large-diameter cutter 2 is disposed on the front surface of this partition part IO. .

Further, at the rear of the outer skin plate 8, a plurality of shield jacks 13 for propelling the shield excavator itself are arranged along the circumferential direction of the outer skin plate 8, and an erector device for assembling the segments 9. 1
4 are provided.

The shield jack 13 has its front end supported by the rear end surface of the fixed blade 11, and is configured to propel the shield excavator itself forward by taking a reaction force to the front end of the segment 9 assembled by the erector device 14. It is configured.

The large-diameter cutter 2 is disposed approximately in the center of the outer skin plate 8, and includes a cylindrical inner skin plate 6 forming an inner shell, and a circular plate that is joined to the front end surface of the inner skin plate 6 and faces the face. It consists of a shaped cutter head 15 and a cylindrical support drum 16 joined to the rear end of the inner skin plate 6.

As shown in FIG. 1, the cutter head 15 has a plurality of parallel front slits 17 (four in this embodiment) facing each other to take in dirt, and each front slit 17... A large number of cutter bits 18... are fixed.

Further, on the circumferential portion of the cutter head 15, protruding in the radial direction,
A plurality of telescopic cutters 19 (two in this embodiment) for excavating the earth are provided at equal intervals. The amount of protrusion of the telescoping cutter 19 is set to a maximum at the position where its tip coincides with the outer circumferential surface of the outer skin plate 8, and so that the tip of the cutter head 15 is aligned with the outer skin plate 8 when the cutter head 15 rotates (not shown). It is controlled steplessly by the control unit.

The inner skin plate 6 is a cylindrical member having an elliptical cross-sectional shape as shown in FIG. 3, and its major axis is formed between the diameter of the cutter head 15 and the groove. Further, as shown in FIG. 2, the inside of the inner skin plate 6 serves as a mud water pressure chamber 3 into which muddy water is pumped, and the irregularly shaped space formed between the inner skin plate 6 and the outer skin plate 8 is It is configured as a mud pressure chamber 5.

The front opening of the mud water pressure chamber 3 is closed by a cutter head 15, and the rear opening is closed by a partition wall 12. At the top of the surface of the partition wall 12 on the mud pressure chamber 3 side,
The end of the water pipe 20 is open, and the end of the mud removal pipe 21 is open below that.

A hole 7 (hereinafter referred to as a side slit) is provided in the peripheral wall of the inner skin plate 6 to communicate the mud pressure chamber 3 and the mud pressure chamber 5 and to take the earth and sand in the mud pressure chamber 5 into the mud pressure chamber 3. ) are provided at intervals along the circumferential direction.

The opening degree of these side grooves 7 can be adjusted by an opening/closing device (not shown). Further, a cutter pit (not shown) is attached around the side slit 7, making it easy to take in earth and sand into the side slit 7.

The cross-sectional shape of the inner skin plate 6 is not limited to an elliptical shape; for example, one side is a perfect circle with the diameter as a boundary and the other side is an ellipse, as shown in FIG. 5, and other shapes. Any non-circular shape such as an egg shape is sufficient.

However, when the inner skin plate 6 rotates, it is not preferable to have a shape that causes too high rotational resistance.

As shown in FIG. 2, the support drum 16 is inserted into a circular drum support hole 23 formed between the fixed blade 11 and the partition wall 12, and is rotatably supported by the drum support hole 23. The rear end portion is connected to a drive motor 25 via a gear 24. A plurality of drive motors 25 are provided along the outer periphery of the support drum 16, and each drive motor 25 is attached to a drive motor support section 26 provided in the same number as the drive motors 25. The drive motor support portion 26 extends rearward from the outer peripheral portion of the partition wall 12 . The support drum 16 is connected to these drive motors 25...
This allows it to rotate around its axis.

In the large-diameter cutter 2, the power of the drive motor 25 is transmitted to the cutter head 15 via the gear 24, the support drum 16, and the inner skin plate 6, and the cutter head 15 rotates, thereby excavating the ground in a circular shape. It looks like this. In this way, the cutter head I5 of this embodiment is supported by the drum support method.

Further, as shown in FIG. 5, small-diameter cutters 4 are provided at the opening of the mud pressure chamber 5, that is, at the four corners of the rectangular outer skin plate 8, respectively. These small diameter cutters 4... have a substantially conical small diameter canterhead 27 (hereinafter referred to as
Head. ) and this.

A cutter shaft 28 extends rearward from the axis of the blade 27 through the fixed blade 11 and is rotatably supported by a bearing (not shown). It consists of a drive motor 30 for a small-diameter cutter that rotates the cutter. The head 27 excavates the face and at the same time stirs the earth and sand in the mud pressure chamber 5 to give fluidity, and this earth and sand passes from the mud pressure chamber 5 through each side slit 7 of the inner skin plate 6 to the mud water pressure chamber 3. It makes it easier to be taken into the world.

According to this small-diameter cutter 4, the power of the small-diameter cutter drive motor 30 is transmitted to the head 27 via the cutter shaft 28, and the head 27 rotates to excavate the ground.

For these small-diameter cutters 4, the excavation range is the irregularly shaped part in the front of the mud pressure chamber 5, excluding the excavation range of the large-diameter cutter 2 inside the outer skin plate 8, as shown in FIG. . In addition, the conical hem 27 is
A face plate type or spoke type may also be used.

In order to excavate a ground using a shield excavator having such a configuration, first, mud water is supplied from the water pipe 20 into the mud water pressure chamber 3 to pressurize the mud water pressure chamber 3, and then a large-diameter cutter is used to excavate the ground. Stabilize the face on the front of the cutter Rad 15 of No. 2.

Next, the erector device 14 applies a reaction force to the frontmost end of the segment 9 assembled on the tunnel peripheral wall, thereby extending the shield jack I3 and propelling the shield excavator itself forward, which had been activated in advance. The large-diameter cutter 2 and the small-diameter cutter 4 are used to excavate the front face, and the fixed blade 11 is used to excavate the tunnel periphery. Earth and sand from this excavation is taken into the mud pressure chamber 3 and the mud pressure chamber 5.

At this time, the earth and sand excavated by the small-diameter cutter 4 and the fixed blade 11 and sent into the mud pressure chamber 5 are transferred to the oval inner skin plate 6 as the cutter blade 15 rotates.
By rotating, the muddy water and earth and sand are stirred and transferred into the muddy water pressure chamber 3 through the side slit 7.

After excavating one segment in this manner, the shield excavator is stopped and at the same time, a new segment 9 is assembled at the front end of the segment 9 inside the shield excavator. On the other hand, the muddy water containing earth and sand taken into the muddy water pressure chamber 7 is discharged to the rear of the tunnel by the mud draining pipe 21. This earth and sand is finally transported to the ground and separated into earth and sand and muddy water, and the muddy water is again supplied into the muddy water pressure chamber from the water pipe.

Furthermore, when the shield excavator is stopped and the rotation of the large-diameter cutter 2 is stopped, the portion of the inner skin plate 6 where the side slit 7 is not formed is positioned upward, or as shown in the figure. Collapse of the crown ground is prevented by closing the side slit 7 located above using a similar opening/closing device.

In this embodiment, the cutter head 15 is supported by a drum support method, so the cutter head 15 is supported by an intermediate support method in which the cutter head 15 is supported by a rotating shaft (for example, a shield excavator as shown in FIG. 6). Compared to the above, the strength for supporting the cutter head 15 is high, and therefore it can be used with a shield excavator having a large diameter.

"Effects of the Invention" As explained above, according to the shield excavator of the present invention, the cross-sectional shape of the cylindrical inner skin plate disposed inside the outer skin plate forming the outer shell is non-circular,
By rotating this inner skin plate along with the rotation of the cutter head, the earth and sand in the mud pressure chamber and the muddy water can be sufficiently stirred, and fluidity can be given to the earth and sand. This makes it easier to take in earth and sand through the holes (side slits) formed in the peripheral wall. Further, since a force is applied to the holes formed in this peripheral wall to push the earth and sand into the mud water pressure chamber side when the inner skin play 1 is rotated, a large amount of earth and sand can be taken in.

Therefore, the shield excavator of the present invention can improve the efficiency of taking in the earth and sand into the mud pressure chamber, and has the effect that the earth and sand can be quickly discharged.

Further, when the cutter head of a large-diameter cutter is supported by a drum support method, the supporting strength of the cutter head is improved, so that it is possible to cope with the increase in the diameter of the shield excavator.

[Brief explanation of drawings]

1 to 4 are diagrams showing one embodiment of the shield excavator of the present invention, in which FIG. 1 is a schematic front view thereof, and FIG.
The figures are a sectional view taken along the line ■-■ in Fig. 1, Fig. 3 is a sectional view showing the inner skin plate of the above embodiment, Fig. 4 is a sectional view showing the small diameter cutter of the above embodiment, FIG. 5 is a sectional view showing another example of the inner skin plate according to the present invention, and FIG.
7 and 7 are views showing a conventional shield excavator, with FIG. 6 being a sectional view thereof, and FIG. 7 being a schematic perspective view of an inner skin plate and a cutter head. ...Mud water pressure chamber, 4 ...Small diameter cutter, ...Mud pressure chamber, ...Inner skin plate, ...Side slit, ・...Outer slit plate, 0 ...' bulkhead, 15 ... cutter head.

Claims (2)

[Claims] (1) A cylindrical inner skin plate that is provided with a partition at the front of a cylindrical outer skin plate that forms a non-circular outer shell, and that is located in front of the partition and that forms an inner shell inside the outer skin plate. By providing this, the interior of this inner skin plate serves as a cylindrical mud pressure chamber through which mud water is pumped, and the irregularly shaped space formed between the inner skin plate and the outer skin plate serves as a mud pressure chamber. A cutter head for excavating the ground in a circular shape is formed integrally with the inner skin plate at the opening of the mud pressure chamber, and a hole is provided in the peripheral wall of the inner skin plate, and the opening of the mud pressure chamber is provided with a hole. A shield excavator having a plurality of small-diameter cutters arranged in a section thereof, the shield excavator characterized in that the cross-sectional shape of the inner skin plate is non-circular. (2) The shield excavator according to claim 1, wherein the cutter head is supported by a drum support method.