JPS5838079Y2 - shield excavator - Google Patents

Description

[Detailed description of the invention] This invention relates to a shield excavator, and its purpose is to effectively prevent the collapse of the face of other mountains while excavating the ground in front of the face chamber of the shield tube. The earth and sand are discharged to the outside by a screw conveyor, and if the excavated earth and sand contains gravel of a size that cannot be discharged by the screw conveyor, this gravel is removed without reducing the collapse prevention effect of the face. To provide a shield excavator which can be extremely easily discharged to the outside.

Figures 1 to 3 show an example of the shield excavator of the present invention. In each figure, 1 is a cylindrical shield tube made of, for example, a steel plate, and a stirring blade 2 is installed inside the shield tube at the front end. A face chamber 4 is formed in which an excavating tool 3 is provided.

The rotating shaft 5 of the excavating tool 3 is inserted into a bearing 7 provided at the center of the rear wall 6 of the face chamber 4, and its rear end is supported by a radial metal bush 8 and a thrust bearing 9.

Reference numeral 10 denotes a hydraulic motor for driving the excavator, and a pinion 12 attached to the rotating shaft 11 of this motor meshes with a reduction gear 13 attached to the rotating shaft 5 of the excavator 3.

Reference numeral 14 denotes a gravel storage chamber that communicates with the face chamber 4, which is provided at the lower part of the rear wall 6 of the face chamber 4, and this gravel storage chamber 14 is equipped with a press-in pipe 15 for extruding mud, a gravel discharge pipe 16, and a screw conveyor. 17
and the outer cylinder 18 of.

This screw conveyor 17 includes an outer cylinder 18 provided with a soil discharge port 19 at one end, and a screw 20 inserted into the outer cylinder.
and a hydraulic motor 21 that rotates this screw 20.
It depends on this.

Further, the gravel discharge pipe 16 is provided with a gate 22 at its front end and a gate 23 at its rear end.
Attach an oil jack 24 to open and close this.

Reference numeral 25 denotes a mud-filling material press-in pipe; 26 denotes an earth-retaining cylinder formed by assembling a large number of segments I made of, for example, steel plates; 27 is installed between the front end of this earth-retaining cylinder 26 and the rear wall 6 of the face chamber 4; 28 is an earth pressure gauge.

To excavate a horizontal shaft underground using the shield excavator shown in FIGS. 1 to 3, a shaft (not shown) is excavated in the stratum G, and the excavation tool 3 is brought into contact with the side wall of this shaft. This is rotated by a hydraulic motor 10 via a pinion 12 and a reduction gear 13, and while a solution of mud making material such as bentonite, CMC, etc. is being forced into the face chamber 4 from a mud making material press-in pipe 25, the excavating tool 3 is used to ground the soil. A horizontal shaft a is excavated in the horizontal shaft a, and at the same time, an oil jack 27 provided between the front end of the earth retaining cylinder 26 and the rear wall 6 of the face chamber 4 of the shield cylinder 1 is extended to extend into the horizontal shaft a. Press-fit the shield cylinder 1.

When the excavation of the horizontal shaft a has progressed to a certain extent in this manner, a large number of earth retaining cylinders 26 are sequentially assembled at the rear end of the shield cylinder 1 to retain earth on the inner circumferential wall of the horizontal shaft a.

Therefore, when carrying out each of the above steps, the excavated earth and sand accumulated in the face chamber 4 and the mud-making material sent through the mud-making material press-in pipe 25 are stirred and mixed by the rotation of the stirring blades 2 to form a highly viscous material. The earth pressure of this mud prevents the front face of the face chamber 4 from collapsing.

In this way, when the amount of mud accumulated in the face chamber 4 increases to a certain extent, the screw conveyor 17 is moved by the hydraulic motor 21.
This mud is discharged to the outside by rotating the screw 20.

Next, when the mud in the face chamber 4 is being discharged by the screw conveyor 17 as described above, as shown in FIG. If the dirt is mixed in and comes out into the gravel chamber 14, mud for extruding gravel is injected into the gravel chamber 14 from the mud injection pipe 15, and this pressure prevents the earth pressure in the face chamber 4 from decreasing. At the same time, the gate 22 is opened with an oil jack 24, and the gravel is press-fitted into the gravel discharge pipe 16 as shown in FIG. 4B, and the gate 23 is opened to discharge the gravel to the outside.

When the gravel has been discharged in this way, as shown in Figure 4C, close the mud injection pipe 15.
The injection of mud for extruding gravel from the screw conveyor 17 is stopped, and the discharge of mud from the screw conveyor 17 is continued.

As mentioned above, the shield excavator of the present invention mixes and stirs the excavated soil that accumulates in the face chamber of the shield tube to form a highly viscous mud, so the earth pressure of this mud effectively collapses the face in front of the face chamber. Not only can this mud be prevented from leaking, but since the viscosity of this mud is high, it can be easily discharged to the outside using a screw conveyor.

If the excavated soil contains gravel that is too large to be discharged by the screw conveyor, the gravel is introduced into a gravel chamber that communicates with the face chamber and used for extruding the gravel. Since mud is forced in, the pressure of this mud not only allows the gravel to be easily discharged to the outside, but also prevents the earth pressure in the face chamber from decreasing due to the earth pressure of the mud for extruding gravel when discharging the gravel. It is something that can be done.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of an embodiment of the shield excavator of the present invention;
2 is a sectional view taken along the line A--A in FIG. 1, FIG. 3 is a side view of a portion thereof, and FIGS. 4A, B, and C are explanatory diagrams of its operation. 4...Face chamber, 1...Shield tube, 2
... Stirring blade, 3 ... Excavation tool, 10,
11.12.13...Device for rotating excavation tool, 25...Mud material press-in pipe, 14...
Gravel chamber, 17... Screw conveyor, 15.
...Mud injection pipe for extruding gravel, 16...Gravel discharge pipe, 22.23...Gate for opening and closing the gravel inlet and gravel discharge port of the gravel discharge pipe, 27・・・・・・
...A device that propels the shield tube.

Claims (1)

[Scope of utility model registration request] A shield cylinder provided with a face chamber in the front, an excavation tool having a stirring blade provided in the face chamber, a device for rotating the excavator tool, a sludge material press-in pipe connected to the above-mentioned face chamber, and the above-mentioned face chamber. a gravel chamber communicating with the gravel chamber, a screw conveyor communicating with the gravel chamber, a mud injection pipe for extruding gravel and a gravel discharge pipe connected to the gravel chamber, and a gravel inlet and a gravel discharge port of the gravel discharge pipe. A shield excavator comprising: gates that open and close gates, and a device that propels the shield tube forward.