JPS6126469Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a shield excavator, and in particular mixes excavated soil and additives on the face plate of the cutter to form a surface to be excavated (hereinafter referred to as "face"). This invention relates to a shield excavator that is designed to prevent the collapse of snails and reduce the load on snails.

[Conventional technology]

In general, shield excavators are already known, in which additives such as bentonite solution are mixed with excavated mud (hereinafter referred to as "sludge"), and the earth pressure of the mixed mud is used to prevent the collapse of the rock face while excavating. ing.

[Problem that the invention attempts to solve]

However, this type of conventional shield excavator is generally configured to mix the sludge and the additive in the cutter chamber formed on the rear side of the cutter face plate, so the additive is evenly distributed to the sludge. It was difficult to mix the water into the water, and it was not possible to sufficiently achieve water stoppage or prevention of face collapse.

On the other hand, as a prior art, there is an excavator 1 (Japanese Patent Application Laid-open No. 18229/1983) as shown in FIG. This digging machine 1
The additive is jetted out near the cutter slit 3 formed on the cutter face plate 2, and the additive is mixed with the cutter slit 3 to the cutter chamber 4.
It is designed so that it can be taken into the system.

By the way, in this excavator 1, the waste excavated by the cutter bit 5 that is not taken into the cutter chamber 4 is located below the gap S formed between the cutter face plate 2 and the face 6. As a result, Sb above the gap S becomes hollow, so even if it were possible to fill the cutter chamber 4 with mixed mud, the collapse of the face 6 would still be unsatisfactory. Prevention cannot be achieved. Moreover, as the excavation machine 1 excavates, the debris that has fallen and accumulated in the lower Sa of the gap S is consolidated by the cutter face plate 2 and acts like a so-called disc brake that brakes the rotation of the cutter face plate 2, so that the load is reduced. There is a problem in that the cutter load is forced to increase.

In particular, since the excavator 1 injects the additive only in the vicinity of the cutter slit 3, it is not possible to supply the additive over the entire area on the cutter face plate 2, and therefore the cutter torque due to the lubricating action of the additive is reduced. Not only is it not possible to expect a reduction in the amount of damage, but also it is not possible to achieve uniform mixing of excavated soil and additives.

Therefore, in view of the problems with conventional shield tunneling machines, the present invention has been devised to effectively solve these problems. The purpose of this invention is to be able to efficiently supply additives to the entire area on the cutter face plate, thereby reliably preventing collapse of the face, and to reduce the load on the cutter as much as possible. It is to provide a shield excavator that can.

[Means for solving problems]

In order to achieve the above object, the present invention provides a shield excavator having a cutter face plate rotatably supported within a cylindrical shield frame, in which the cutter face plate and the surface to be excavated are attached to the outer periphery of the cutter face plate. A flange extending in the direction of excavation is formed to define a hollow chamber between the two, and a cutter bit is provided on the front surface of the cutter face plate to protrude from the end of the flange via a cutter spoke. A cutter slit is formed that communicates the hollow cutter chamber provided on the rear side with the hollow chamber, and an annular additive supply passage is formed on the inner wall of the shield frame to surround the flange, and the additive is supplied to the flange. A plurality of additive introduction ports are formed to communicate with the hollow chamber from the agent supply passage, and the excavated soil and the additive are mixed in the hollow chamber.

〔Example〕

A preferred embodiment of the present invention will be described in detail below with reference to FIG. 2 and subsequent drawings.

In FIG. 2, reference numeral 1 denotes a cylindrical shield frame constituting the outer shell of the shield tunneling machine, and a cutter 11 is rotatably provided at the front end of the opening. This cutter 11 is a shield frame 10
A cylindrical cutter frame 12 rotatably mounted inside the cutter frame 12, a flat cutter face plate 13 integrally formed to cover the front side (excavation direction side) opening of this cutter frame 12, and this cutter face plate. 1
The cutter bit 15 is mainly composed of a plurality of cutter bits 15 attached to the cutter spokes 14 as shown in FIG. In particular, the cutter face plate 13 is formed slightly inside the opening end of the shield frame 10, and a hollow space 17 is formed between the cutter face plate 13 and the face 16 by a flange portion 13a extending in the excavation direction from the outer periphery of the cutter face plate 13. It has come to form compartments. In addition, Katsutabitsu 15 has face 16.
Of course, it is provided so as to protrude from the open end of the shield frame 10 so that it can be excavated.

The cutter frame 12 is supported by the shield frame 10 via a bearing 18 and connected to a drive machine (not shown), so that the cutter 11 is rotationally driven. In addition, a partition wall 20 is provided at the rear opening end of the cutter frame 12 to define a hollow cutter chamber 19 on the rear side of the cutter face plate 13.
is provided via a sealing member 21, and this partition wall 2
0 is a screw conveyor 22 which is a means of transporting earth and sand.
is attached so that its carrying-in portion 22a faces into the cutter chamber 19.

On the other hand, as shown in FIGS. 2 and 3, the cutter face plate 13 is formed with a cutter slit 23 that matches the tip of the cutter bit, and is configured to take the waste excavated by the cutter bit 15 into the cutter chamber 19. .

An annular additive supply passage 24 surrounding the flange portion 13a of the cutter face plate 13 is formed on the inner wall near the front opening end of the shield frame 10. That is, this passage 24 connects the inner wall or inner peripheral wall of the shield frame 10 on the fixed side and the flange portion 13 of the cutter frame 12 on the rotating side.
a pair of annular seal members 25a, 25b between
It consists of a so-called slip ring that is partitioned by interposing a slip ring. The passage 24 has a partition wall 2
An additive injection pipe 27 led from a working space 26 on the inner rear side of the shield frame 10 bordering on 0 and arranged along the inner wall of the shield frame 10 is connected to it, and an additive such as a bentonite solution is introduced thereinto. Configured to be injected. Also, cutter face plate 1
The flange portion 13a of No. 3 is provided with a plurality of (six in the illustrated example) inlets 28 that communicate with the passage 24 and introduce additives onto the cutter face plate 13. It is configured to eject inward in the radial direction.

In addition, the reference numeral 29 in FIG. 2 indicates the shield frame 10.
The propulsion jack provided therein, 30, is a segment assembled within the borehole.

Next, the operation of the above embodiment will be described.

In FIG. 2, when the cutter frame 12 is rotationally driven while propelling the shield frame 10, the face 16 is excavated by the cutter bit 15 which rotates together with the cutter frame 12, and the gap is first divided into sections between the face 16 and the cutter face plate 13. It is accommodated in the hollow chamber 17 that is formed. Then, the waste stored in the hollow chamber 17 is taken into the cutter chamber 19 from the cutter slit 23 by the earth pressure generated by the excavator as it excavates, and is transferred to the rear outside of the shield frame 10 by the screw conveyor 22. It will be carried out.

By the way, when excavating a soft soil area where the face 16 is likely to collapse, the excavation is performed while mixing an additive such as a bentonite solution into the sludge. In this case, the additive is injected into the passage 24 via the injection tube 27;
It is ejected from this passage 24 through an inlet 28 onto the cutter face plate 13 and is supplied. By rotating on the cutter face plate 13, the sludge is mixed with the additive evenly or in the required amount and turned into mud, and this mixed mud is taken into the cutter chamber 19 from the cutter slit 23, and then the screw It is carried out via the conveyor 22 to the outside.

In particular, since the additive is ejected from the flange portion 13a of the cutter face plate 13 along the cutter face plate 13 inward in the radial direction,
The additive can be efficiently and evenly supplied over the entire area on the cutter face plate 13, and the shear and the additive can be sufficiently mixed on the cutter face plate 13 by its rotational force. Therefore, face 16
A layer of mixed mud consisting of sludge and additives is formed between the face plate 13 and the face plate 13, and since no cavity is formed between the face plate 16 and the face plate 13, no water leaks from the face plate 16. Water and collapse of the face 16 can be reliably prevented. Moreover, since the top of the stub face plate 13 is covered with mixed mud, even if earth pressure acts on the stub face plate 13 as the excavation progresses, the lubricating action of the additive can reduce the stub load as much as possible.

In the above embodiment, a plurality of stirring members may be formed on the cutter face plate 13 to extend forward in the axial direction, thereby promoting mixing with the shear additive.

[Effect of idea]

In summary, according to the present invention, the following effects can be obtained.

(1) Additives are introduced into the hollow chamber formed between the cutter face plate and the cutting face through the plurality of additive inlet ports provided on the flange of the cutter face plate, so that there is no shearing of the additives in the hollow chamber. can be sufficiently mixed.

(2) Therefore, it is possible to form a layer of mixed mud made by mixing sludge and additives between the face and the stub face plate, thereby stably holding the face and preventing its collapse. This can be reliably prevented.

(3) Furthermore, since the top of the cutter face plate is covered with the mixed mud, the load on the cutter can be reduced as much as possible due to the lubricating effect of the additive and the fluidity of the mixed mud.

(4) An annular additive supply passage is formed on the inner wall of the shield frame to surround the flange, and the additive is supplied directly into the hollow chamber. This eliminates the need for a defective additive inlet pipe that inhibits the flow of additives.

[Brief explanation of the drawing]

FIG. 1 is a schematic side sectional view of a shield tunneling machine exemplified as a conventional example, FIG. 2 is a side sectional view of a shield tunneling machine according to a preferred embodiment of the present invention, and FIG. 3 is a front view thereof. In the figure, 10 is a shield frame, 13 is a cutter face plate, 13a is a flange thereof, 14 is a cutter spoke, 15 is a cutter bit, 17 is a hollow chamber, 2
3 is a cutter slit, 24 is an additive supply passage, 2
8 is an inlet.

Claims (1)

[Scope of utility model registration request] In a shield excavator having a cutter face plate rotatably supported within a cylindrical shield frame, a hollow chamber is defined between the cutter face plate and the surface to be excavated on the outer periphery of the cutter face plate in the direction of excavation. A cutter bit is provided on the front surface of the cutter face plate and protrudes from the end of the flange portion via a cutter spoke, and a hollow cutter chamber provided on the rear side of the cutter face plate and a cutter bit are provided on the front surface of the cutter face plate and protrude from the end of the flange portion through cutter spokes. A cutter slit communicating with the hollow chamber is formed, an annular additive supply passage surrounding the flange portion is formed on the inner wall of the shield frame, and a plurality of additives are formed in the flange portion communicating with the hollow chamber from the additive supply passage. A shield excavator characterized in that a shield excavator is configured to form an agent inlet to mix excavated soil and an additive in the hollow chamber.