JP2011214255A - Structure of shield machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shield machine capable of maintaining the surface of a soil pressure stabilizing liquid at a fixed level even if the shield machine starts from the ground or the semi-underground.SOLUTION: The structure of the shield machine provided with a cutter head 2 on a front face of an outer shell 1 and a partition wall 3 behind the cutter head 2 includes a rotary blade 4 arranged on the partition wall 3 on the side of the cutter head 2, a rotary shaft 42 arranged parallel to a center shaft of the shield machine to impart rotation to the rotary blade 4, and a power source to impart rotation to the rotary shaft 42 in a direction opposite to the rotary direction of the cutter head 2.

Description

  The present invention relates to a shield machine structure, and more particularly to a shield machine structure starting from the ground and a semi-underground.

In the earth pressure type shield machine, a partition is provided on the back of the cutter surface, and the cutter chamber between the face and the partition is filled with a kneaded mixture of the earth and sand and earth pressure stabilizing liquid.
At that time, while balancing the pressure of the earth and sand in the cutter chamber and the face pressure of the face, the face is stabilized and the earth and sand matching the amount of excavation is discharged by a screw conveyor or the like and advanced.

JP 2006-46058 A.

In the shield machine that starts from the ground, the kneaded mixture of excavated earth and sand and the earth pressure stabilizing liquid can be filled in the cutter chamber between the partition wall and the face.
However, when a part starts from underground, the upper part of the shield machine is exposed to the ground, so there is no target face above the cutter surface.
For this reason, the height of the liquid level of the kneaded mixture of earth and sand and earth pressure stabilizing liquid is not constant due to the rotation of the cutter face plate and spokes, and it becomes difficult to keep the earth pressure of the face constant. There is a risk that the face will collapse.
If a rocking cutter is used to solve such a problem, the liquid level can be stabilized.
However, in such a structure, since the cutter reciprocates in the same place, the earth pressure stabilizing liquid and the earth and sand cannot be sufficiently stirred, and it becomes difficult to plastically fluidize the earth and sand to stabilize the face. .

  In order to solve the above-described problems, the shield machine structure of the present invention is a shield machine having a cutter head on the front surface and a partition wall behind the cutter head, provided on the cutter head side of the partition wall. A rotating blade, a rotating shaft that gives rotation to the rotating blade, parallel to the central axis of the shield machine, and a power source that can rotate the rotating shaft in the direction opposite to the rotating direction of the cutter head It is characterized by.

Since the structure of the shield machine of the present invention is as described above, the following effects can be obtained.
<1> Even when excavating at a position where the upper part is exposed from the ground surface, the liquid surface height is constant and a constant earth pressure can be applied to the face, so that the face can be prevented from collapsing.
<2> Since the rotor blades are rotated in the opposite direction to the cutter head in the cutter chamber, the earth and sand in the cutter chamber and the earth pressure stabilizing liquid can be mixed efficiently, and stable excavation can be performed. Become.
<3> It is possible to reduce the number of fixed blades that are usually arranged in the partition wall for stirring the earth pressure stabilizing liquid and the excavated earth and sand.

The exploded explanatory view of the example of the structure of the shield machine of the present invention. FIG. Explanatory drawing of an operation state. Explanatory drawing of the operation state of another Example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

<1> Overall configuration.
The shield machine of the present invention relates to a shield machine having a cutter head 2 on the front surface of an outer shell 1 and a partition wall 3 behind the cutter head 2.
The shape of the outer shell 1 can be either cylindrical or rectangular.
Moreover, although the cutter head 2 demonstrates the spoke 21 type shield machine in the Example of a figure, it can also employ | adopt also about a face plate type shield machine.

<2> Rotor blade.
There is a gap between the cutter head 2 and the partition wall 3.
The rotor blade 4 is positioned within this interval.
The rotor blade 4 is configured by radially arranging a plurality of blades 41 around a rotating shaft 42.
The outer diameter of the rotary blade 4 is smaller than the outer diameter of the cutter head 2.
The angle of the wing plate 41 surface with respect to the partition wall 3 surface can be changed according to earth and sand, soil quality, and construction conditions.
The rotor blades 4 are arranged at one place or a plurality of places of the partition wall 3.

<3> A rotating shaft.
The rotary blade 4 is configured by arranging a plurality of blades 41 radially, and a rotation shaft 42 is positioned at the center of the blades 41 group.
The rotating shaft 42 is an axis arranged in parallel to the central axis of the shield machine.
The rotation of the shaft 42 gives the plurality of blades 41 a rotation around the rotation shaft 42. Further, the rotating shaft 42 may be located at a position eccentric from the center of the blade 41 group.

<4> A rotational drive source.
A rotational drive source 43 is arranged on the back surface of the partition wall 3, that is, on the wellhead side.
This drive source 43 provides rotation to the rotating shaft 42.
The drive source 43 is a power source capable of giving a rotation in a direction opposite to the rotation direction of the cutter head 2 to the rotation shaft 42.
Furthermore, the rotational speed of the drive source 43 can be changed according to the change in the liquid level of the earth pressure stabilizing liquid.

<5> Other embodiments. (Fig. 4)
The rotation of the rotor blade 4 can be obtained from the center shaft 22 at the center of the spoke 21 of the cutter head 2 via the gear 23 without being obtained from the unique drive source 43.
In this case, if the rotation of the center shaft 22 is directly transmitted to the rotary blade 4 via the gear 23, the rotational directions of both are reversed.
Further, it is possible to adopt a structure that gives a change in rotational speed and torque by a configuration through a gear such as a speed reducer or a gear.

<6> Operation.
The shield machine of the present invention is effective when a part of the shield machine is exposed to the ground as described above.
As in the conventional shield machine, the shield machine is advanced by extending the jack by taking the reaction force in the rear segment group.
At that time, the earth pressure stabilizing liquid is discharged from the periphery of the central axis of the cutter head 2 to the face side.
At the same time, the rotating blade 4 is rotated in the direction opposite to the rotating direction of the cutter head 2.
Then, the kneaded mixture of the earth and sand that moves by the rotation of the cutter and the earth pressure stabilizing liquid can be moved in the opposite direction in the cutter chamber, and as a result, the liquid level can be kept constant.
The rotational speed of the rotary blade 4 can be adjusted while observing the state of the slope of the earth and sand surface taken into the cutter chamber.
The earth and sand kneaded with the earth pressure stabilizer in the cutter chamber is taken into the outer shell 1 from the mud 31 and carried out of the mine.

1: outer shell 2: cutter head 3: partition wall 4: rotating blade 41: slat 42: rotating shaft 43: action source

Claims (1)

A shield machine with a cutter head on the front of the outer shell and a partition wall behind the cutter head,
A rotor blade provided on the cutter head side of the partition;
A rotation axis parallel to the central axis of the shield machine that gives rotation to the rotor blades;
Constructed with a drive source that can give the rotation axis rotation in the direction opposite to the rotation direction of the cutter head,
Shield machine structure.

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