JPS5835759Y2 - Shield type tunnel excavator - Google Patents

Description

[Detailed explanation of the idea] This proposal concerns a shield type tunnel boring machine.

As shown in Fig. 1, a conventional shield type tunnel excavator is provided with a bulkhead 2 in front of a shield body 1, and a cutter disk 3 in front of the bulkhead 2. It is compressed between the shield body 2 and the bulkhead 2, and is transported rearward by a screw conveyor 4 disposed within the shield body 1 so as to communicate with the lower part of the bulkhead 2.

A gate 5 is installed at the rear soil discharge port of the screw conveyor 4 to adjust the opening of the soil discharge port, thereby consolidating the excavated soil and stopping water inside the screw conveyor 4, thereby preventing the face from collapsing. I try to do that.

However, in the conventional shield type tunnel excavator, since the back surface of the cutter disk 3 and the front surface of the partition wall 2 are parallel, the excavated soil from the face is consolidated more than necessary in the parallel chamber, and the lower part Therefore, the excavated soil is not discharged and becomes clogged in the parallel chamber, causing the cutter disk to be unable to rotate and making it impossible to excavate.

In many cases, such a phenomenon cannot be avoided even if a fluidizing agent is injected through the injection pipe 6 disposed in the parallel chamber. Therefore, in order to prevent the excavated soil from clogging in the parallel chamber, the screw conveyor If the number of rotations is increased to reduce the degree of compaction in the parallel chamber, a space will be created above the parallel chamber, and the ground above the face will collapse, causing the passage to cave in and cause a serious accident.

In addition, since the rear soil discharge port of the screw conveyor 4 has an opening gate adjustment system, it is common to discharge soil in a half-open state during excavation. Groundwater gushes out from the mouth, and at the same time excavated soil is discharged regardless of the rotation speed of the screw, reducing the compaction of the excavated soil in the parallel chamber and causing the collapse of the ground.

The purpose of this proposal is to eliminate such defects by shaping the earth-cutting consolidation chamber formed between the partition wall in front of the shield body and the cutter head into a downwardly expanding shape, and forming a hole in the lower part of the earth-cutting consolidation chamber. A shield type tunnel characterized in that a screw conveyor that communicates with the shield body is arranged upwardly at the rear, and a compressed air injection device and an airtight earth removal device are installed at the rear upper part and rear lower part of the screw conveyor, respectively. Regarding the excavator, its purpose is to prevent the cutter disc from being unable to rotate due to over-consolidation of the excavated soil in the excavated soil consolidation chamber formed between the cutter disc and the bulkhead, and to prevent the cutter disc from being able to rotate due to the excavated soil in the excavated soil consolidation chamber formed between the cutter disc and the bulkhead. An object of the present invention is to provide an improved shield type tunnel excavator that prevents underground water from gushing out.

In this case, as mentioned above, the excavated soil consolidation chamber formed between the partition wall in front of the shield body and the cutter head is formed in a downwardly expanding shape, so it is difficult to attach the excavated soil to the partition wall. This prevents the excavated soil from becoming more compacted and clogged than necessary, and therefore there is no risk of the cutter disc becoming unable to rotate.

In addition, the lower screw conveyor of the downwardly expanding soil consolidation chamber is in communication with the screw conveyor, and the screw conveyor discharges the excavated soil from below the soil consolidation chamber.
Since the excavated soil in the excavation and consolidation chamber is discharged while moving downward in a consolidated state, the excavator of the present invention can excavate easily collapsible ground without causing it to collapse.

Furthermore, in this case, the screw conveyor is installed upwardly in the shield main body, and an airtight soil removal device is installed at the rear lower part of the screw conveyor, so that it can remove a fixed amount of soil while blocking the groundwater pressure from the face and the soil. can be discharged to atmospheric pressure.

Furthermore, in the present invention, a compressed air injection pipe is installed at the rear upper part of the screw conveyor, and compressed air is sent from the injection pipe into the screw conveyor to push the moisture in the excavated soil to the face and discharge it. The water content of the soil is reduced, making it easier to dispose of it using trolleys and dump trucks.

The present invention will be described below with reference to illustrated embodiments.

A partition wall 12 is provided in front of the shield body 11, and a cutter disk 13 is provided in front of the partition wall 12, and both 12.1
An excavation and consolidation chamber 14 is formed between the three.

The cutter disk 13 has an excavating cutter bit 15 attached to its front surface, is tilted toward the rear at the lower part, and has a shaft 16 protruding from the rear surface that rotatably penetrates the partition wall 12. Gear 1 mounted on the rear end of
7 meshes with a pinion 19 mounted on the drive shaft of a motor 18 mounted on the shield body 11, so that the cutter disk 13 is rotated by the motor 18.

Further, the partition wall 12 is formed as an inclined wall that is spaced backward from the back surface of the cutter disk 13 as it goes downward, and therefore, the earth excavation consolidation chamber 14 formed between the cutter disk 13 and the partition wall 12 has a downwardly expanding shape. It is composed of

In the excavated soil consolidation chamber 14, an injection pipe 20 for injecting an excavated soil fluidizing agent is attached to the partition wall 12 as an auxiliary means for allowing the excavated soil to flow downward while being consolidated.

In addition, a screw conveyor 21 is installed so as to communicate with the lower part of the earth excavation and consolidation chamber.
is arranged in the shield main body 11 so as to be inclined toward the rear and upper part.

A watertight and airtight hopper 23 is attached to the discharge port 22 at the rear lower part of the screw conveyor 21, and discharges a fixed amount of soil under atmospheric pressure while maintaining soil pressure and water pressure by compacting the excavated soil in the screw conveyor 21. ing.

The screw conveyor 21 is isolated from atmospheric pressure by an outer cylinder 24, and the screw is driven by a motor 25 mounted on the outer cylinder 24.

Further, the outer cylinder 24 has a screw conveyor 2 at the rear upper part.
A compressed air injection pipe 26 is installed for supplying compressed air into the excavated soil to push out water in the excavated soil being carried out by the screw conveyor 21 to the front of the partition wall 12 to make excavated soil that can be easily carried out.

In the embodiment shown in FIG. 2, the hopper 23 is equipped with a sphere 28 with a gap that slides and rotates inside the hopper casing by a motor 27, and when the gap opens upward as shown in the figure. At the same time, a fixed amount of excavated soil falls from the soil discharge port 22, and when the sphere 28 rotates 180 degrees, the gap opens downward and the excavated soil in the concave cavity falls.

Therefore, the excavated soil can be discharged in a fixed amount while maintaining the soil pressure and water pressure within the screw conveyor 21.

Note that the hopper 23, the motor 27, and the spaced sphere 2
8 constitutes the above-mentioned airtight soil removal device.

3 and 4 respectively show other embodiments of the airtight earth removal device. In the embodiment shown in FIG. 3, the hopper 23a is of a rotary feeder type, and in the embodiment shown in FIG. The hopper 23b is configured in a gate type.

The illustrated shield type tunnel excavator is constructed as described above, so that when excavating a face by rotating the cutter disk 13, the cutter disk 13 is inclined toward the lower rear, so that the excavator The earth and sand in the front upper part is difficult to collapse, and the excavated soil excavated by the cutter slide 13 is taken into the excavated soil consolidation chamber 14 formed between the partition wall 12 and compacted. Since the chamber 14 is formed in a downwardly curved shape, it is difficult for excavated soil to adhere to the partition wall 12, and there is no possibility that a clogging phenomenon will occur and the cutter disk 13 will not be able to rotate.

The excavated soil in the excavated soil consolidation chamber 14 moves downward in a consolidated state, and is carried out by the screw conveyor 21 toward the rear and upper part of the shield body 11, without collapsing the face. It becomes possible to excavate with an excavator.

The excavated soil carried out by the screw conveyor 21 is transported to a watertight and airtight hopper 23 installed at the lower rear of the screw conveyor 21.
The water is discharged to the atmospheric pressure side while blocking groundwater pressure and earth pressure from the face.

At this time, by injecting compressed air into the screw conveyor 21 from a compressed air injection pipe 26 installed at the rear upper part thereof, the screw conveyor 21 pushes out the water contained in the excavated soil being carried out to the front of the partition wall 12. to reduce the moisture content of the earth and sand discharged from the hopper 23,
This facilitates the carrying out process using trolleys, dump trucks, etc.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal side view of a conventional shield type tunnel excavator, Fig. 2 is a longitudinal side view of an embodiment of the shield type tunnel excavator according to the present invention, and Figs. 3 and 4 are respectively airtight earth removal devices. FIG. -11... Shield body, 12... Bulkhead, 13... Cutter disk, 14...
・Earth excavation consolidation room, 21...screw conveyor,
22... Soil discharge port, 23... Watertight and airtight hopper 26... Compressed air injection pipe.

Claims (1)

[Scope of utility model registration request] The earth excavation consolidation chamber formed between the partition wall in front of the shield body and the cutter head is shaped to expand downward, and a screw conveyor that communicates with the lower part of the earth excavation consolidation chamber is arranged rearward inside the shield body. A shield type tunnel excavating machine characterized in that a compressed air injection device and an airtight soil removal device are installed at the rear upper part and the rear lower part of the screw conveyor, respectively.