JPS624624Y2 - - Google Patents

Description

[Detailed description of the invention] The invention relates to a shield tunneling machine,
The purpose is to prevent the dirt taken into the pressure chamber from adhering to the wall surface of the excavated soil intake chamber formed within the shield body, that is, the cutter pressure chamber for preventing the face from collapsing, causing an arching phenomenon. The purpose is to prevent this from having a negative impact on shield excavation.

As shown in FIG. 1, some types of shield tunneling machines have an inner cylinder 3 disposed inside a shield body 2 having a cutter head 1 on the front side, and a bulk head fixed concentrically to the inner cylinder 3. An earth removal device 5 consisting of a screw conveyor is attached to 4. The earth and sand receiving section 5A of the earth removal device 5 is
The bulkhead 4 opens into an excavated soil intake chamber (cutter pressure chamber) 6 defined inside the shield body 2.

In such a shield excavator, the shield body 2 is propelled while the cutter head 1 is rotated, and the earth and sand taken into the excavated earth and sand intake chamber 6 is accordingly released to the atmosphere by the earth removal device 5. An operation to discharge is performed. In that case, the excavated soil intake chamber 6 must maintain an internal pressure sufficient to prevent the face from collapsing even during continuous soil removal operation.
For this purpose, a pressure gauge (earth pressure gauge, water pressure gauge, etc.) 7 is attached to the bulkhead 4, and the detected value of this pressure gauge is associated with the control operations of the earth removal device, propulsion device, etc.

However, with conventional shield tunneling machines, the first
As shown in the figure, since the bulkhead 4 was arranged parallel to the front surface of the cutter head 1, that is, perpendicular to the direction of propulsion of the shield body 2, the excavated soil was taken into the chamber 6. Earth and sand 8 adheres to the front surface of the bulkhead 4 and gradually grows as the shield body 2 moves forward, causing an arching phenomenon. The occurrence of such a situation not only causes a false indication on the pressure gauge 7 attached to the bulkhead 4 and a decrease in the propulsion speed due to a decrease in soil removal efficiency, but also causes a reduction in the propulsion jack 9 in order to increase the propulsion speed.
This makes it necessary to increase the extrusion pressure, which causes a vicious cycle in which arches due to the earth and sand grow further. And finally cutter head 1
Torque over occurs, forcing suspension of propulsion.

The present invention has been devised in view of the above, and embodiments thereof will be described below with reference to FIGS. 2 to 5.

11 is a shield body, 12 is an inner cylinder, and between the shield body 11 and the inner cylinder 12, a surrounding wall 14 fixed to the cutter head 13 is rotatably supported by a bearing/seal 15, etc. A cutter head 13 is operatively connected to a drive motor 16 installed on the shield body 11. These points are the same as the conventional one explained in FIG. A bulkhead 17 is fixed to the inner cylinder 12, and the bulkhead 17 is arranged so as to be inclined with its upper part pushed out toward the front side of the shield body 11. An earth removal device 18 consisting of a screw conveyor is attached to this bulkhead 17. In this case, as shown in FIG.
The excavated soil intake chamber 19 is formed in the surrounding wall 14 between the excavated soil removal device 3 and the bulkhead 17 and is opened upward, and the axis X of the soil removal device 18 is set at 90 degrees or more with respect to the bulkhead 17. The mounting angle θ is maintained. Furthermore, there are pressure gauges 2 such as earth pressure gauges and water pressure gauges on the top of the bulkhead 17.
0 is attached, and a cutter 21 is installed near it.
will be provided. As is clear from FIGS. 3 and 4, the rod 22A of the cylinder (cylinder device) 22 supported by the inner cylinder 12 is connected to the bulkhead 17.
The cutter 21 is fixed to the tip of the cutter 21, and a slide support 23 is provided between the rod 22A and the bulkhead 17 to prevent leakage of water pressure and entrapment of earth and sand. 23A indicates a sealing material. As the cutter 21, a vertically flat cutter as shown in FIG. 4 or a cross-shaped cutter as shown in FIG. 5 may be adopted as appropriate. In addition, 24 in FIG. 2 indicates a shield propulsion jack.

According to this embodiment, since the bulkhead 17 is inclined as described above, the excavated earth and sand intake chamber 19
The earth and sand in the inner upper part moves downward along the bulkhead 17 in accordance with the propulsion of the shield main body 11, and is introduced into the earth and sand receiving section 18A of the earth removal device 18. Therefore, by injecting a soil conditioner as necessary, the arching phenomenon caused by the adhesion of earth and sand to the upper part of the bulkhead 17 can be completely prevented, erroneous indications on the pressure gauge 20 can be eliminated, and the soil removal effect can be improved. If soil or sand adheres to the bulkhead 17,
If there is a risk of adhesion, remove the cylinder 22.
The cutter 21 is moved in and out as appropriate. This breaks down the adhering soil and prevents adhesion.

As is clear from the above explanation, in the present invention, the bulk head is arranged at an angle, so that it is possible to prevent the occurrence of arching inside the inner cylinder.
Furthermore, since the cutter is installed in the bulkhead via a cylinder device, even if an arching phenomenon occurs, the arching phenomenon can be eliminated by moving the cutter in and out using the cylinder device, thus improving soil removal efficiency. You can improve your performance.

[Brief explanation of the drawing]

Fig. 1 is a schematic vertical side view of a conventional example, Figs. 2 to 5 show an embodiment of the present invention, Fig. 2 is a schematic longitudinal side view, and Fig. 3 is an enlarged vertical cross-sectional view of main parts. ,
Figure 4 is a cross-sectional view taken along line A-A in Figure 3;
The figure is a front view of a modified example of the cutter. 11...Shield body, 12...Inner cylinder, 17...
...Bulkhead, 18...Earth removal device, 18A...
Sediment reception department, 19...excavation earth and sand intake room.

Claims (1)

[Scope of utility model registration request] In the inner cylinder provided in the front part of the shield body,
A bulkhead is provided to define an excavated soil intake chamber facing the face, and a soil receiving portion of an earth removal device that opens in the excavated soil intake chamber is fixed to the bulkhead, the bulkhead comprising:
The shield is arranged so that its upper part is pushed out toward the front side of the shield main body, and a cylinder device is installed in the upper position outside the excavated earth and sand intake chamber in the inner cylinder, and its rod is inserted into the bulkhead, and This shield excavator is characterized by a cutter attached to the tip of this rod.