JPS6214229Y2 - - Google Patents

Description

[Detailed description of the invention] The invention relates to a shield tunneling machine,
The purpose of this is to prevent clayey soil from adhering and growing on the wall surface of the excavated earth and sand intake section configured inside the machine, which would obstruct smooth earth removal and eventually excavation.

When excavating a cohesive soil layer, a sandy soil layer, etc. using a shield excavator, the adhesion and growth of sediment occurs on the wall surface of the earth and sand intake section inside the machine, which is a factor that impedes smooth excavation work. In particular, a solution to this problem has long been desired for muddy water pressurization shields intended for excavation in clayey and sandy soils.

This invention can obtain particularly good results when applied to muddy water pressurized shields, but we also propose a shield excavator that is sufficiently adaptable to earth pressure type and other types of shields, and its implementation will be described below. Explain an example.

In Figures 1 and 2, 1 is the shield body;
2 is a cutter head placed in front of it.
The cutter head 2 has an opening 3 in the center and a plurality of slits 4 extending radially around the opening 3, and a number of cutter bits 5 are fixed to the edges of the slits 4 on the surface thereof. Opening 3 on the back side of cutter head 2
One end of a cylindrical shaft 6 is concentrically fixed to the periphery of the cylindrical shaft 6, and the rear end of the cylindrical shaft 6 is supported via a bearing 8 on an annular partition 7 fixed to the shield body 1. be done. Therefore, a dirt intake chamber 9 is formed between the cylindrical shaft body 6 and the shield body 1. The cylindrical shaft body 6 has a dirt port 10 in its peripheral wall, and its rear end is connected to a rotational drive device (hydraulic motor) 12 provided in the shield body 1 via a gear device 11. A support cylinder 13 is disposed at the rear inside the cylindrical shaft 6 and is fixed to the shield body 1 by a mounting member 14, and a seal bearing 15 is provided between the support cylinder 13 and the cylindrical shaft 6. is interposed. 16
indicates a screw drilling rig. In the illustrated example, the screw excavation device 16 includes a bearing device 18 supported by a support cylinder 13 via a seal device 17, a rotating shaft 19 cantilevered on the bearing device 18, and a screw blade integrated with the rotating shaft 19. 20, a bit 21 fixed to the tip of the rotating shaft 19, and a rotating shaft driving device 22. The bearing device 18 is the rotating shaft 1
9 is allowed to move forward and backward in the axial direction within a certain stroke, and a reciprocating jack 23 for causing this movement to move forward and backward is fixed to the rear end surface of the support cylinder 13 and the rotary shaft drive device 22. It is interposed between the fitting 24 and the fitting 24 . As the rotating shaft 19 moves forward and backward as the reciprocating jack 23 expands and contracts, the bit 2 at the tip of the rotating shaft 19 moves forward and backward.
1 moves forward and backward between the front side and the back side of the cutter head 2, and its maximum protrusion amount is indicated by δ in FIG.
On the other hand, a mud feeding water pipe 25 is connected to the upper part of the sediment intake chamber 9 through the partition wall 7, and a mud drainage water pipe 26 is connected to the lower part thereof through the partition wall 7, and an agitator 27 is provided. .

The rotation of the rotary drive device 12 is transmitted to the cutter head 2 via the gear device 11 and the cylindrical shaft 6, and the face ground is excavated by the rotation and propulsion of the cutter head 2. Furthermore, the rotation shaft 19, screw blade 20, and bit 21 are rotated in the same direction as the cutter head 2 or in the opposite direction by the operation of the rotation shaft drive device 22. The earth and sand excavated by the cutter head 2 enters the earth and sand intake chamber 9 through the slit 4, and the earth and sand excavated by the screw excavator 16 enters the inside of the cylindrical shaft body 6 through the opening 3. On the other hand, since muddy water is forced into the earth and sand intake chamber 9 through the mud water pipe 25, the excavated earth and sand mixes with this muddy water and pressurizes the face with the muddy water. Agitator 2 for soil removal
This is done by transporting the earth and sand stirred in step 7 as a slurry to the ground through the drainage pipe 26. Inside the cylindrical shaft body 6, a screw blade 20
Since the cutter head 2 is rotating in the same direction or in the opposite direction, the earth and sand taken in through the opening 3 and the earth and sand or muddy water introduced from the earth and sand intake chamber 9 through the earth and sand passage 10 are mixed and further crushed. . In this way, the earth and sand that has entered the cylindrical shaft 6 is mixed and crushed into fine particles, and is prevented from adhering to the inner wall surface of the cylindrical shaft 6 and the inner wall surface of the earth and sand intake chamber 9 on the discharge side. If the earth and sand are not finely crushed, the earth and sand become lumps, quickly settle and accumulate, and grow attached to the inner wall surface of the earth and sand intake chamber 9). At this time, it is recommended to arbitrarily select an appropriate relative rotational speed of the screw excavator 16 with respect to the cutter head 2, or to reciprocate the screw blade 20 back and forth with the reciprocating jack 23 in order to prevent the adhesion of clayey soil. greatly helps. Furthermore, by operating the reciprocating jack 23 to project the bit 21 to the front of the cutter head 2, the center of the face can be cored and excavated, which is effective for excavating hard layers.

It is also possible to propose various modifications in order to enhance the effect of crushing clay soil within the cylindrical shaft body 6.
FIG. 3 shows a screw blade 20 of a screw excavator 16 cut out at multiple locations to form slits 28, and a rod-shaped projection 29 provided on the cylindrical shaft body 6, which enhances the crushing effect by the cooperation of the two. showing something. Figure 4 also shows screw blade 2.
0 is abolished and a protrusion 30 is provided on the discontinued part, while a protrusion 31 is also provided on the cylindrical shaft body 6.
This figure shows the aim of creating a crushing and cutting effect on cohesive soil through the joint action of the two. In the devices shown in FIGS. 3 and 4, the effect of crushing clayey soil is significantly enhanced, so the reciprocating jack 23 and the sealing device 1
It becomes possible to omit elements such as 7.

As is clear from the above explanation, according to the present invention, soil enters the cylindrical shaft directly from the opening, and dirt enters the upper sediment intake chamber from the slit and then enters the cylindrical shaft from the soil port. The earth and sand once moves into the earth and sand intake chamber below and is discharged from there, but the earth and sand are mixed and crushed by the screw blade inside the cylindrical shaft and are crushed into fine pieces, and the screw blade is sent out into the cylinder. The earth and sand in the shaped shaft body is forcibly sent out into the earth and sand intake chamber on the discharge side (in other words, the screw blade rotates and the earth and sand are sent backward, but because the rear end is blocked, the earth and sand are not sent to the rear). (The collected sediment moves forward along the wall surface of the cylindrical shaft and is forcibly sent into the sediment intake chamber from the sediment port.) By stirring the inside of the sediment intake chamber, The adhesion of earth and sand to the walls of the containment chamber is significantly reduced, so earth is removed smoothly and excavation efficiency is improved.

Although the muddy water pressure shield has been described in the embodiment, the present invention can be effectively applied to other types of shields, such as earth pressure shields.

[Brief explanation of the drawing]

Fig. 1 is a front view of an embodiment of the present invention, Fig. 2 is a longitudinal sectional side view of the same, Fig. 3 is a longitudinal sectional side view of a main part of a modification, and Fig. 4 is a longitudinal sectional side view of a main part of another modification. . 1...Shield body, 2...Katsuta head, 3
...Opening, 4...Slit, 6...Cylindrical shaft, 9
... Sediment intake room, 10 ... Sediment outlet, 12 ... Rotation drive device, 16 ... Screw excavation device, 19
... Rotating shaft, 20 ... Screw blade, 22
... Rotating shaft drive device, 23 ... Reciprocating jack.

Claims (1)

[Scope of utility model registration request] A cylindrical shaft body having a dirt port in the peripheral wall is fixed concentrically to the back of the cutter head, which has an opening in the center and a slit for taking in dirt around the cutter head. A screw excavator having a screw blade is disposed concentrically within the cylindrical shaft body, and is pivotally supported on the shield body forming an earth and sand intake chamber between the shield body and connected to its rotary drive device. A shield excavator, characterized in that a bearing of this screw excavator is fixed to the shield main body.