JPS61294092A - Airtight earth-removing device for shielding machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention is applicable to shield construction methods, propulsion construction methods,
This relates to an airtight soil removal device for shield machines used in small-diameter propulsion methods, etc.

<Conventional technology> As a tunnel excavation technology, there is a shield method in which the tunnel face is stabilized using pressurized air, muddy water, mud, etc.

In these construction methods, excavation is carried out by limiting the areas that require pressurization to only the face of the shield, and the delivery of segments, assembly, backfill injection, earth and sand removal, etc. are performed under atmospheric pressure.

By the way, if the pressurized earth and sand in the face is discharged as it is, there is a risk that the earth and sand will erupt due to the pressure difference.

As a technology to prevent this eruption of soil, the soil discharge port of screw conveyor A is currently equipped with (a) a flapper valve.

(b) Equipped with rotary feeder C. (Fig. 6) (c) Equip slide gate B. (Figure 7) (d)
Measures are being taken such as installing rotary dischargers.

<Problems to be Solved by the Present Invention> The above-described technology for preventing the eruption of earth and sand has the following problems.

(a) Since the flapper valve uses a counterweight or hydraulic jack to counteract the pressure of the face, it is not possible to prevent sudden eruptions.

(b) In the case of the type equipped with a slide gate B, sudden eruptions cannot be prevented because a hydraulic jack D is used to open and close the slide gate B.

(c) In the case of the type equipped with a rotary feeder C, it works effectively for ejection, etc., but the work space is narrow because it is installed below the screw conveyor A (and the work efficiency such as loading the segments and opening number is extremely difficult). There are many cases where it gets worse.

(d) A rotary discharger has a larger outer diameter than a screw conveyor, and has the same disadvantages as when equipped with a rotary feeder.

OBJECT OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and provides a shield that can reliably prevent the eruption of earth and sand with a simple structure and can further expand the working space. The purpose is to provide an airtight soil removal device for machines.

<Example> An example of the present invention will be described below with reference to the drawings.

<A> Airtight soil removal device (FIG. 1) The airtight soil removal device is located at the tail end side of the screw conveyor 2, and is composed of a soil collecting plate 3 and a rotary blade 6 having a high-pressure fluid injection function.

At the tail end of the +4 cylinder 210 that constitutes the screw conveyor 2, there is a hydraulic motor 10 for driving the screw blades 22.
Place.

The screw blades 22 are not formed over the entire area of the rod 23, but are formed to a position slightly before reaching the soil discharge port 24 opened at the tail end of the outer cylinder 21, and between the end of the screw blades 22 and the hydraulic motor 10. leaves the rod 23 exposed.

A soil collecting plate 3 is disposed in the outer cylinder 21 immediately in front of the soil removal l] 24, and a space S is left in the outer cylinder 21 to obliquely shield it.

The soil collecting board 3 can be a single board arranged at an angle, or a cylinder with one end cut off diagonally.

In short, it is only necessary to form an inclined surface 31 within the outer cylinder 21 at the tail end of the screw blade 22 so that the internal space can be squeezed upward.

A hole for passing the rod 23 through the plate surface of the soil collecting plate 3,
” A V-shaped opening is opened on the S side of the two-part space.

The V-shaped opening size may be formed to be equal to the partition angle θ of a unit space partitioned by rotary blades 6, which will be described later.

A plurality of rotary blades 6 are provided radially protruding in the axial direction on the rod 23 inside the outer cylinder 2 which forms the soil discharge port 24 in a part of the circumference. (In the case of this embodiment, there are four sheets.) The present invention has screw conveyors 20 lots 23 and coaxial
One of the features is that a rotary blade 6 is formed at I-.

As a result, the space within the outer cylinder 21 that accommodates the rotary blades 6 is partitioned by the rotary blades 6, and a unit space S1 is formed in the space surrounded by each two rotary blades 6.

<2> High-pressure fluid injection means An injection port 5 is provided on the circumferential surface of the rod 23 exposed in the unit space S1, and high-pressure air, water,
Alternatively, the configuration is such that a mixed fluid of these can be ejected.

For example, the rod 23 can be used as a means for ejecting these fluids.
Each injection [
15 can be adopted.

The fluid is injected into each unit space S1 in each unit space S.
This is to prevent the dirt 1 filled in the rotary blade 6 from adhering to the rotary blade 6.

Therefore, depending on the degree of adhesion of the earth and sand 1, the fluid is selected and injected continuously or intermittently.

<E> Other embodiments Rotary blade 6 provided at the tail end of the screw conveyor 2
It is also possible to use one in which the outer cylinder 21 for enclosing the rotary blade 6 is formed independently from the screw conveyor 2.

That is, the tail end of the screw blade 22 and the hydraulic motor 10
A special rod with a rotary blade 6 provided therebetween and a special outer cylinder are connected by screwing or welding.

Next, the soil removal method will be explained.

(1) The earth and sand 1 is sequentially moved toward the earth collecting plate 3 by the screw blades 22 rotated by the hydraulic motor 10 inside the earth and sand retention outer cylinder 21 .

The earth and sand 1 that has moved at a constant speed reaches the slope 3 of the earth collecting plate 3.
Temporarily stays in the space adjacent to 1.

(2) Filling and compaction of earth and sand Since the space of the earth collecting plate 3 is narrowed toward the upper space S, as the amount of accumulated earth and sand 1 continues to increase, the speed of the accumulated earth and sand increases, It flows into the unit space Sl partitioned by the rotary blades 6.

When the accumulated sediment 1 flows into the unit space Sl, a more effective sand plug phenomenon (
Water stoppage effect phenomenon due to filling compaction on plasticization occurs).

Note that the earth and sand 1 supplied from the screw conveyor 2 may be allowed to flow directly into each unit space Sl without providing the earth collecting plate 3.

(3) Since the earth discharge rotary blade 6 rotates while sharing the rod 23 coaxial with the screw blade 22, the earth and sand 1 that has flowed into the unit space S1 is rotationally transferred downward.

The earth and sand 1 stored in the unit space Sl and continuing to move naturally falls from the earth discharge port 24 due to gravity.

At this time, high-pressure air, water, etc. are ejected from the injection port 5 into the unit space Sl, so that the earth and sand 1 stored in the unit space S can be cleanly discharged.

The soil 1 discharged from the soil discharge port 24 is, for example,
The material is transported under normal pressure by a belt conveyor placed directly below it.

As explained above, each time each unit space S1 passes through the upper space S, a large amount of earth and sand 1 is sent instantaneously from the screw conveyor 2 side to fill each unit space S1.

Since each unit space S1 forms an independent space, the earth and sand 1 can be moved downward while being completely blocked from the face side.

Therefore, when the earth and sand 1 naturally falls from the earth discharge port 24, there is no fear of eruption.

<Effects> Since the present invention is as explained above, the following effects can be obtained.

(a) Since the airtight earth removal device is formed coaxially with the screw conveyor and housed within the outer cylinder, there is no need to protrude an airtight earth removal device etc. from the outer periphery of the screw conveyor as in the past.

Therefore, a sufficient working space can be secured and a favorable working environment can be achieved.

(b) As mentioned above, in addition to eliminating the protrusion of the outer circumference of the screw conveyor, the rod of the rotary vane can share the rod of the screw vane and the drive shaft of the hydraulic motor, and each rod has the same or almost the same diameter. Since it can be formed into a large diameter, it is effective for small diameter shields.

(c) Since the discharge section of the screw conveyor is narrowed down by the earth collecting plate, the water stopping effect of the conventional sand plug phenomenon is further enhanced.

(d) Since the discharge section of the screw conveyor is narrowed down, the flow speed becomes faster, and a sufficient amount of earth and sand can be taken into the unit space partitioned by the rotary blades.

(e) Standardization can be achieved by dividing the airtight soil removal device of the present invention.

(F) When discharging soil, water and air can be injected from the rotary blade rod to reliably prevent soil from adhering.

Therefore, the soil removal efficiency is improved.

[Brief explanation of drawings]

Figure 1 1 Overall explanatory diagram of the airtight soil removal device according to the present invention 2
Figure: Perspective view of the airtight soil removal device Figure 3: Vertical sectional view thereof Figure 4; Cross-sectional view of TV-TV in Figure 3 Figure 5; Cross-sectional view of V-V in Figure 3 Figure 6.7 :Explanatory diagram of conventional technology

Claims (1)

[Scope of Claim] A shield machine having a structure in which excavated soil is discharged by a screw conveyor, in which a rotary blade installed coaxially with the drive shaft of the screw conveyor is housed in a cylinder on the tail end side of the screw conveyor, An airtight soil removal device for a shield machine that has a soil discharge port on the side of the tube that houses the blades.