JPH0457840B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a large-diameter shield machine used when constructing a horizontal shaft such as a tunnel underground.

(Prior art) An earth pressure type mechanical shield machine used for tunnel excavation is a type that mixes the excavated soil taken inside and the injected mud material such as bentonite, and thereby presses down the face. There is something.

In this shield construction method, the excavated soil is injected into the excavated soil and mixed in the chamber of the shield machine to convert the excavated soil into mud, and the earth pressure from this mud is used to stabilize the face while excavating. The mixing mechanism that mixes the excavated soil and the soil material is important for turning excavated soil into mud.

FIG. 2 shows a conventional example of this type of shield machine, and the mixing in a chamber 20' defined by a partition wall 2' is usually carried out by a cutter wing 14' of a large rotary excavator 13' . This is done by a kneading blade 16' provided on the back side of the kneading blade 16'.

In this case, since the kneading blade 16' is provided behind the cutter wing 14', it rotates at the same speed as the rotation speed of the cutter wing 14'. By the way, with the current manufacturing technology of shield machines, the rotational speed of the excavating tool is generally 20 m/s in the tangential direction of the outermost part due to the durability of the excavating tool.
It is designed to run at around 30m/min. For this reason,
As shield machines became larger in diameter, chamber 2
The mixing effect near the inner periphery within 0' is worse than that near the outer periphery, which has the drawback that it is difficult to convert excavated soil into uniform mud.

(Object of the invention) The present invention has been proposed in view of the above points, and its purpose is to excavate with a rotary excavator that has a bulkhead at the front of the shield machine body and excavates the face. In a shield machine that presses the face by filling a mud-making chamber formed by a face, a shield tube, and a partition wall with earth and sand, the rotary excavator has a mixing blade attached to the immediate portion thereof, and A plurality of mixing devices consisting of small-diameter wings with mixing blades protruding from the front of the bulkhead are installed in the rear mud-making chamber, and the mixing area by these mixing devices is circular, and a portion of the mixing device is circular. By overlapping each other, substantially the entire area in the mud-making soil chamber can be stirred, so that the excavated soil in the mud-growing soil chamber can be stirred in the outer periphery,
To provide a shield machine capable of easily and quickly converting the inner circumference into mud.

(Structure of the invention) The present invention will be described below with reference to the drawings.

Figures 1A to 1C show an embodiment of the present invention. In the figure, 1 is a cylindrical shield cylinder with a relatively large diameter. An extending disk-shaped partition wall 2 is formed.

Reference numeral 3 denotes a small first rotary excavator which is rotatably provided in the center of the front end opening of the shield cylinder 1 and slightly protrudes forward, and which functions as a so-called cutter. It is provided through the center part, and the tip part is exposed and protrudes forward, and the tip part is provided with a fishtail-shaped central bit 5, and the rear end part is connected to the drive motor 7 via a gear mechanism 6. a boss 9 provided between the central bit 5 at the tip of the center shaft 8 and the front end of the rotation transmitting member 4; a base end connected to the boss 9; A plurality of cutter wings 10 extending radially, a large number of bits 11 protruding from the front of the cutter wings 10, and a mixing blade 12 protruding rearward from the immediate rear of the cutter wings 10. It is composed of. Note that, depending on the case, the kneading blade 12 may not be necessary.

Further, a large-sized second rotary excavator 13 for excavating the peripheral area is provided behind the first rotary excavator 3 , and the second rotary excavator 13 emits radiation toward the outer circumference of the shield tube 1. A plurality of cutter wings 14 extending from the cutter wing 14, a bit 15 protruding from the front part of the cutter wing 14, and a mixing blade 1 protruding from the immediate rear part extending toward the inside of the shield cylinder 1.
6, and the rotatable drum-shaped rotation transmission member 4, in which the proximal end of the cutter wing 14 is provided at the distal end, and the rear end is connected to the drive motor 18 via a gear mechanism 17. and is configured to be able to rotate independently of the first rotary excavator 3 .

Reference numeral 19 designates a plurality of rotatable mixing devices installed in a mud chamber 20 defined by the inner wall at the front of the shield tube 1 and the front surface of the partition wall 2 so as not to collide with each other. It consists of a small-diameter wing 22 having mixing blades 23, whose mixing area is circular, and some of the wings overlap each other to create a mud-making soil chamber 20.
It is provided so that substantially the entire area within the chamber can be stirred.

That is, the shaft 21 penetrating the partition wall 2
At the tip of the shaft 21, long and short wings 22a, 2 are provided, for example, in a substantially cross shape and protrude within the chamber 20 in a radial direction with respect to the shaft 21.
spokes 22 consisting of 2b and these wings 2
2 and a mixing blade 23 protruding from the rear of the mixing blade 23,
The rear end of the shaft 21 behind the bulkhead 2 and the rotation transmission member 4 are connected via a gear mechanism 24, so that when the rotation transmission member 4 rotates once, the wing 22 rotates several times according to the gear of the gear. The kneading device 19 has a shaft 21.
It is also possible to drive them independently by mutually independent drive devices configured by connecting a drive motor (not shown) to the rear of the unit.

Reference numeral 25 denotes a discharge device of a well-known construction whose front end is provided in a manner that allows communication with the lower part of the chamber 20, and includes a cylindrical body 26 and a screw conveyor 27 rotatably provided within this body 26. We are prepared.

In the above shield machine, each of the drive motors 7 and 18 is fixed to frames 28 and 29 which are appropriately provided behind the partition wall 2. Further, the rotation transmission member 4 is rotatably supported by support members 30, 31, and 32 provided at the center of the partition wall 2, the frame 29, etc., and the center shaft 8 is rotatably supported by the rotation transmission member 4, the frame 28, etc. The supporting member 30 and the shaft 21 of the bulkhead 2
A sealing member 33 for preventing mud from entering behind the partition wall 2 is appropriately provided at the support portion and the like.

Next, the operation of the present invention will be explained.

Excavation of the earth is performed by first and second rotary excavators 3 and 13 . That is, when the drive motor 7 is driven, the rotation of the drive motor 7 is transmitted to the center shaft 8 via the gear mechanism 6, and the center bit 5 and cutter wing 10 rotate.
The central part of the face is excavated by the first rotary excavator 3 . In this case, a swivel joint 35 to which a mud material injection pipe 34 is connected is provided at the rear end of the center shaft 8.
An injection pipe 8a is formed in the center of the center shaft 8, and the mud material is injected to the outside from the mud material injection port 8b at the tip of the center shaft 8. Although not particularly shown in the drawings, it is also possible to extend an injection pipe into the cutter wing 10 and inject the mud material from the cutter wing 10 to the outside.

Further, when the drive motor 18 is driven, the rotation of the drive motor 18 is transmitted to the drum-shaped rotation transmission member 4, and the cutter wing 14, which is longer than the cutter wing 10, rotates. 13 rotates. Further, it penetrates through the inside of the rotation transmission member 4 and is connected to the center shaft 8 by a swivel joint 37, is connected to the soil material injection pipe 8a inside the center shaft 8, and has a tip extending into the cutter wing 14. Mud material injection pipe 38
It is also possible to inject more soil material.

Thus, both the excavated soil and the poured mud material are taken into the mud making soil chamber 20, and a first stage of mixing is performed by the mixing blade 16 provided at the rear of the cutter wing 14. In addition, the wings 22 of the kneading device 19 provided in plurality at the rear of the cutter wing 14, the spoke 2
The mixing blade 23 provided immediately after the cutter wing 14 further mixes the mud that has been mixed in the first stage by the mixing blade 16 provided immediately after the cutter wing 14, and excavates it. Converts earth and sand into mud. In addition, in the shaft 21 provided with the mixing blades 23, there is an injection pipe 2 for injecting the mud material.
1a is installed from the tip to the rear end,
It is configured such that mud-making soil material can be injected into the mud-making soil chamber as needed from a mud-making soil material injection pipe (not shown) connected via a swivel joint 36. Here, the wing 22 of the kneading device 19
The trajectories drawn by the trajectories are circular, as shown in FIG. 1C, and some of the trajectories overlap each other. Therefore, although it is not possible to cover the entire soil chamber, the first stage of mixing is performed by the mixing blade 16 installed at the rear end of the cutter wing 14, so the trajectory of the wing 22 Even if there is some deviation from the range, there is no problem in turning the excavated soil into mud. It goes without saying that if the ground contains a large amount of silt or clay, the soil material may not be injected.

As is well known, if the shield cylinder 1 is pushed forward by a drive means such as a jack (not shown), earth pressure is generated, which can press down the face, and the soil is suitable for pressing the face. As the shield machine moves forward while maintaining pressure, the chamber 20
The excavation work can be carried out while discharging the mud inside through the discharging device 25 .

(Effects of the Invention) As described above, according to the present invention, earth and sand excavated by a rotating excavator having a bulkhead at the front of the shield machine body and excavating the face are formed by the face, the shield tube, and the bulkhead. In a shield machine that fills the mud-making soil chamber and presses the face, the rotary excavator has a mixing blade attached to the immediate portion thereof, and a kneading blade that protrudes in front of the bulkhead in the mud-making soil chamber at the rear of the rotary excavator. A plurality of mixing devices each consisting of small-diameter wings having mixing blades are provided, and the mixing area by these mixing devices is circular, and some of the mixing areas overlap each other, so that approximately the inside of the mud-making soil chamber is By being provided so that the entire area can be stirred, there is an advantage that the excavated soil in the mud cultivation chamber can be converted into mud easily and quickly across the outer and inner peripheral parts.

Further, by providing a plurality of mixing devices having small-diameter mixing blades, it is possible to reliably and uniformly mix the excavated soil in the mud making chamber with a small mixing torque.

[Brief explanation of the drawing]

1 shows an embodiment of the present invention, A is a front view, B is a partially sectional side view, C is a sectional view taken along line A--A in FIG. 2, and FIG. 2 is a conventional example. DESCRIPTION OF SYMBOLS 1... Shield tube, 2... Bulkhead, 3 ... First rotating excavator, 5... Center bit, 8... Center shaft, 10... Cutter wing, 11... Bit, 12... Mixing wing , 13 ...Second rotary drilling tool, 14...Cutter wing, 15...Bit, 16...Kneading and mixing wing, 19 ...Kneading and mixing device, 20...Chamber, 22...Wing, 2
3... Mixed wings.

Claims (1)

[Scope of Claims] 1. The shielding machine has a partition wall at the front part and fills the earth and sand excavated by a rotary excavator that excavates the face into the mud chamber formed by the face, the shield tube, and the partition. In a shield machine for suppressing a face, the rotary excavator has a mixing blade attached to its immediate portion, and a small-diameter wing protruding in front of the bulkhead and having a mixing blade is installed in the mud-making chamber at the rear of the rotary excavator. A plurality of kneading and mixing devices are provided, and the kneading area by the kneading and mixing devices is circular, and some of the kneading devices overlap each other, so that substantially the entire area in the mud making soil chamber can be stirred. A shield machine that is characterized by being