JPS6160236B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tunnel excavating machine in which an excavating tool rotated by a drive device is rotatably supported at the front part of the excavating machine main body.

Next, an example of a conventional shield tunneling machine of this type will be explained with reference to FIG.

A rotary excavator 33 driven by a drive shaft (for example, a hydraulic motor) 32 is rotatably supported at the front of the excavator main body 31, and a direction correction jack 34 is mounted on a wall near the rear of the excavator main body 31. is set up. A screw conveyor 35 is mounted inside the excavator main body 31 to carry out earth and sand excavated by the rotary excavator 33 to the rear. A propulsion pipe 36 is connected to the rear end of the excavator main body 31, and a belt conveyor 37 for receiving and carrying out earth and sand discharged from the screw conveyor 35 is installed inside the propulsion pipe 36.

In this seal excavator, the propulsion pipe 36 is generally inserted by a propulsion jack installed in the starting shaft. The earth and sand excavated by the rotary excavator 33 is carried to the rear by a screw conveyor 35, and then discharged outside the mine by a belt conveyor 37, a trolley (not shown), or the like. For this reason, when a small seal excavator is used to excavate a tunnel with a diameter of 1 m or less, there is no working space inside the mine, and maintenance of the machine becomes almost impossible. Also, it is not practical to use small belt conveyors, trolleys, etc.
There is no effective means to transport excavated soil out of the mine. Furthermore, since no workers are allowed inside the mine, it is extremely difficult to check whether excavation, soil removal, and loading onto belt conveyors, etc., are proceeding smoothly.

An object of the present invention is to provide a tunnel excavating machine that can smoothly excavate even small-diameter tunnels.

The tunnel excavating machine of the present invention rotatably supports a rotary excavating tool having a larger outer diameter than the excavating machine main body and a tunneling pipe connected to the excavating machine main body at the front part of the excavating machine main body, and adds viscosity to the excavated earth and sand near the excavation surface. An injection means for injecting liquid is provided, and a pressure holding frame body is installed on the excavation surface of the starting shaft to prevent the release of earth and sand pressure in the annular passage formed between the excavation hole, the excavation machine body, and the propulsion pipe. The pressure holding frame is provided with a soil discharge port, and a vibrator that vibrates the excavator body is installed inside.

Embodiments of the present invention will be described below with reference to FIGS. 2 to 5 and FIGS. 6a and 6b.

A rotary excavator 1 having an outer diameter larger than the outer diameter of the propulsion pipe 5 connected to the excavator main body 2 and its rear end is rotatably supported at the front of the excavator main body 2. That is, the rotating shaft 6 of the rotary excavator 1
is a bearing 18 attached to the shaft center of the excavator main body 2,
It is rotatably supported by 19 and 20, and its rear end is connected to a drive device (not shown) installed in the starting shaft 17. A pusher ring 3 is attached to the rear end of the excavator main body 2, and a direction correction jack 4 disposed along the outer grain is attached to this. The propulsion tube 5 is connected to the rear end of the pusher ring 3. The direction correction jack 4 is for correcting the direction of the excavator main body 2 by taking the reaction force with the propulsion tube 5.

The rotating shaft 6 is provided with an injection path 9 for injecting a viscosity imparting liquid such as bentonite into the earth and sand excavated from the ground 10 by the rotary excavator 1. A pressure detector 8 for detecting earth and sand pressure near the rotary excavator 1 is attached to the front wall of the excavator body 2, and a support wall inside the excavator body 2 is equipped with a pressure detector 8 for detecting earth and sand pressure in the vicinity of the rotary excavator 1. A vibration exciter 7 is installed. The vibrator 7 includes an eccentric shaft 7a and an electric motor 7b for rotating the eccentric shaft 7a.
It is made up of.

A starter jack 16 for inserting the propulsion pipe 5 is installed in the starting shaft 17, and a pressure holding frame 13 is attached to the excavated surface of the starting shaft 17. The pressure holding frame 13 is a sealed frame that prevents the earth and sand pressure from being released in the annular passage 12 formed between the excavation hole and the propulsion pipe 5, and includes a pressure holding frame that detects the earth and sand pressure of the discharged earth. A pressure detector 14 is installed, and an on-off valve (not shown) is installed.
A soil discharge port 15 with a soil discharge port 15 attached thereto is connected. The starting shaft 17 is a place where the main push jack 16, the power device of the excavator, etc. are installed, and where the propulsion pipe 5 is connected, soil is removed, etc.

FIG. 4 shows an embodiment in which a vibrator 7 is installed at one location on a support wall fixed inside the excavator main body 2.
When the vibrator 7 is driven, the eccentric shaft 7a rotates, the vibrator 7 vibrates due to the centrifugal force of the eccentric shaft 7a, and the vibration is transmitted to the excavator body 2 via the support wall inside the excavator body 2. is given.

The form of vibration of the excavator main body 2 changes depending on the mounting position of the vibrator 7 and the number of vibrators 7 driven. FIG. 5 shows four vibrating machines 7 7-1, 7-2, and 7- arranged vertically and horizontally symmetrically around the center _O1 of the excavator body 2.
3, 7-4, and an example of the vibration form of the excavator main body 2 in this example is shown in No. 6a.
This will be explained with reference to FIG. 6b.

In FIG. 5, the eccentric directions of the eccentric shafts 7a of the vibrator 7 are all in the same direction (leftward in the figure), and
Assuming that the rotations of the vibration exciters 7-1 and 7-4 on the table are synchronized, an example of the vibration form is as follows.

A When all four vibration exciters 7-1 and 7-4 are driven in the same direction at the same time, the excavator main body 2 vibrates in a direction perpendicular to the center line _O2 of the propulsion tube 5.
That is, as shown in FIG. 6c, the vibration form is such that the center O ₂ of the excavator main body 2 revolves around the center line O ₂ of the propulsion tube 5 with the amplitude e as a radius.

B Rotate the vibrator 7-1, 7-3 clockwise, vibrator 7-
2, 7-4 to the left, the center O ₁ of the excavator main body 2 is located at the propulsion pipe 5, as shown in Fig. 6b.
It vibrates with an amplitude e in the horizontal direction with respect to the center line _O2 , and the amplitude in the vertical direction is zero.

When vibration is applied to rotary excavation in this way, the 6th a.
In the vibration mode shown in the figure, the excavation diameter is an excavation diameter that is an extra excavation diameter e on one side over the entire circumference of the excavator main body relative to the excavation diameter D of the rotary excavation tool 1. In addition, if a vibration mode as shown in Fig. 6b is used for rotary excavation, the excavation diameter will be the major axis D.
+2e, it becomes an ellipse with a short axis D, and the west side e in the long axis direction
The shape is an over-excavated shape, which is the same as the over-excavated shape when correcting the direction in the horizontal direction, making it easier to correct the direction.

This tunnel excavation machine excavates a hole larger than the outer diameter of the propulsion pipe 5 by rotating the rotary excavator 1 while vibrating the rotary excavator 1 and the excavator main body 2 using the vibrator 7. As a result, an annular passage 12 is formed between the outer periphery of the excavator main body 2 and the propulsion pipe 5 and the excavated hole. During excavation, a viscosity imparting liquid is injected into the excavated soil from the injection path 9, and the rotation of the rotary excavator 1 and vibrations of the rotary excavator 1 and excavator body 2 generated by the vibration exciter 7 impart viscosity to the excavated soil. The liquid is stirred and mixed to continuously form high clay viscous liquid mixed earth and sand, and the vicinity of the rotary excavation tool 1 is filled with the viscous liquid mixed earth and sand. When thrust is applied to this region of viscous liquid mixed earth and sand through the front part of the excavator main body 2, the viscous liquid mixed earth and sand 11 that is continuously formed is transferred to the annular passage 1.
Pass through 2 and move to the rear, that is, to the starting shaft side.

The properties of the excavated soil passing through the annular passage 12 can be easily changed by adjusting the concentration and injection amount of the viscosity imparting liquid. In addition, if there is solid matter such as gravel in the excavated soil that cannot pass through the annular passage 12, the vibration of the excavator main body 2 generated by the vibrator 7 causes the solid matter such as gravel to be buried in the ground. Therefore, the discharged soil that is forced to the rear does not contain solid matter such as gravel, and the annular passage 12 is not blocked by solid matter such as gravel.

In this way, the vibration caused by the vibrator 7 is transmitted to the rotary excavator 1.
In addition to reducing the excavation resistance of excavated soil, it improves the stirring and mixing efficiency of excavated soil and viscosity imparting liquid, and also buries gravel in the ground to make the discharged soil uniform, thereby improving the flow of excavated soil. It acts to smooth the process. Note that the vibration exciter 7 can be installed not only in the excavator main body 2 but also in any part of the propulsion pipe 5 as needed (in case the annular passage is clogged with gravel etc. and the flow is poor). The flow resistance of the excavated earth and sand flowing inside the excavated soil can be reduced.

In addition, since the excavator main body 2 and the propulsion tube 5 propel a layer of highly viscous liquid-mixed soil filling the annular passage 12, the frictional resistance between the outer peripheral surface of the propulsion tube 5 and the ground 10 is significantly reduced. Nari, Motoshi Jatsuki 1
6 thrust can be reduced. Furthermore, since the direction correction of the excavator main body 2 by the direction correction jack 4 is no longer restricted by the ground 10,
It can be done easily.

According to the invention described above, the following effects can be obtained.

(1) Since there is no need for workers to work inside the tunnel, tunnels with an excavation diameter of around 1 m or less can be easily excavated.

(2) The frictional resistance between the ground and the outer periphery of the propulsion tube can be significantly reduced, and the thrust of the main push jack can be reduced. As a result, the digging distance can be increased.

(3) Since solid objects such as large gravels that cannot pass through the annular passage 12 can be buried in the ground and left in the ground as the excavation progresses, a special gravel removal device is not required.

(4) By selecting the vibration form, it is possible to secure the amount of excess excavation in the direction that requires direction correction, making direction correction very easy.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional side view showing an example of a conventional seal excavator, FIGS. 2 and 3 are cross-sectional side views showing an embodiment of the present invention, and FIG. 4 is the same as that shown in FIG.
5 is a sectional view corresponding to FIG. 4 showing different mounting modes of the vibration exciter according to the present invention, and FIG.
6b are explanatory diagrams showing examples of different vibration forms by the vibrator of FIG. 5. 1... Rotating excavator, 2... Excavation machine body, 3...
Push-shearing, 4...Direction correction jack, 5...
...Propulsion tube, 6... Rotating shaft, 7... Vibrator, 7a...
... Eccentric shaft of the vibrator, 7b ... Electric motor that rotates the eccentric shaft, 8 ... Pressure detector, 9 ... Injection path, 10
... Earth, 11 ... Viscous liquid mixed earth and sand, 12 ... Annular passage, 13 ... Pressure holding frame, 14 ... Pressure detector, 15 ... Earth discharge port, 16 ... Main push jack, 17 ... …Start shaft.

Claims (1)

[Claims] 1. A rotary excavator having a larger outer diameter than the excavator main body and a propulsion pipe connected thereto is rotatably supported at the front of the excavator main body, and an injection means for injecting a viscosity imparting liquid into the excavated earth and sand near the excavation surface. established,
A pressure holding frame body is installed on the excavation surface of the starting shaft to prevent the release of earth and sand pressure in the annular passage formed between the excavation hole, the excavator body, and the propulsion pipe, and the pressure holding frame body is provided with an earth discharge port. A tunnel excavating machine characterized by having a vibration exciter installed inside the excavating machine to give vibration to the excavating machine body.