JP2862836B2 - Two-stage shield machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-stage shield machine (hereinafter simply referred to as a machine). More specifically, a small-diameter shield main body is coaxially arranged in a large-diameter shield main body so as to be able to expand and contract, so that the tunnel diameter can be reduced and excavated from the middle of a tunnel or the like. Regarding the excavator.

[0002]

2. Description of the Related Art In recent years, the construction of tunnels, common trenches, and the like has often been carried out by a shield method. May have to change. In one example, in the construction of a new subway line or the like, a station building requiring a large-diameter tunnel and a track section that may be a small-diameter tunnel may be continuously excavated. In such a case, a so-called two-stage excavator (also called a parent-child excavator) that can change the excavation diameter of the tunnel (exclusively reducing the diameter) during excavation is used.

In this excavator, a small-diameter inner shield body (hereinafter, also referred to as a child shield) is accommodated in a large-diameter outer shield body (hereinafter, also referred to as a parent shield as appropriate) in a coaxial and nested manner. In addition, excavation of the parent shield is stopped when moving from the large-diameter tunnel to the small-diameter tunnel, and the child shield is started from the tip of the parent shield to excavate the small-diameter tunnel.

[0004] As such a two-stage excavator, those disclosed in the following documents are known. That is,
JP-A-1-94193, JP-A-3-66897, JP-A-3-161694, JP-A-3-19
No. 7791, JP-A-3-250196, JP-A-3-11597, JP-A-5-10086, JP-B-60-38794, JP-A-3-326.
No. 89, Japanese Unexamined Utility Model Publication No. 3-32690, Japanese Unexamined Utility Model Application Publication No.
No. 32692, Japanese Patent Publication No. 2-44996, and the like.

[0005] Some of these excavators are equipped with a feed and discharge mud pipe and a conveyor for discharging excavated earth and sand backward, respectively, on the parent shield and the child shield. But,
If the parent shield is to be equipped with a mud pipe or a conveyor, a corresponding space is required, and the diameter difference between the parent shield and the child shield must be increased.

Further, the parent shield is provided with a unique drive for rotating and driving the parent shield cutter disk (cutter ring), and the child shield is provided with a unique drive for rotating and driving the child shield cutter disk. There are things. Even in such an excavator, since a corresponding space is required in the parent shield, the diameter difference between the parent shield and the child shield increases.

On the other hand, when the diameter is gradually changed in tunnel excavation for a transmission line, a sewer, or the like, it is difficult to employ a shield having a large difference in diameter.

In view of the above, the feed / discharge pipe and the conveyor are extended from the rear only to the cutter chamber of the child shield,
There has been proposed an excavator in which only the child shield is provided with a cutter disk rotation drive, and both the parent and child cutter disks can be connected and separated so that the child shield rotation drive can rotate both cutter disks.

Such an excavator is shown in FIGS.

The excavator 51 shown in FIG. 6 has a structure in which a cutter chamber 52a of a child shield 52 and a cutter chamber 53a of a parent shield 53 are isolated as shown in the figure (FIG. 6B). That is, an outer peripheral ring 54 is covered on the outer periphery of the cutter disk 52b of the child shield 52, and the outer periphery of the cutter chamber 52a of the child shield is separated from the cutter chamber 53a of the parent shield by the cone plate 55. As a result, both shields 5
When two and 53 are excavating together, the parent shield 5
The earth and sand excavated by the cutter disk (cutter ring) 53b of No. 3 does not enter the cutter chamber 52a of the child shield having the earth and sand discharge facility, but is immediately clogged in the cutter chamber 53a of the parent shield, and excavation of the cutter ring 53b. Since the efficiency is significantly reduced, the overall efficiency of the excavator is also reduced.

In addition, for the purpose of solving such a problem, excavators 61 and 71 shown in FIGS. 7 and 8 have been proposed.

The excavator 61 shown in FIG.
In order to allow the cutter chamber 62a of the parent shield 63 to communicate with the cutter chamber 62a of the parent shield 63, the child shield 62
The cone plate is removed from the outer periphery of the cutter chamber 62a. By doing so, the earth and sand excavated by the cutter ring 63b of the parent shield smoothly flows into the cutter chamber 62a of the child shield (arrow A in the figure), and is discharged by a mud pipe or a conveyor (not shown). In other words, the main machine 61 has one cutter chamber common to the parent and child shields.

However, in the machine 61, FIG.
(A) As shown in FIG.
a, the surrounding ground (mainly the upper ground) collapses into the cutter chamber 62a when the child shield 62 is separated from the parent shield 63 and excavated alone (arrows in the figure). B) There is a risk. In this case, not only does the excavation efficiency of the excavator 61 decrease, but also there is a possibility that the collapse of the ground may adversely affect the above-ground structure.

The excavator 71 shown in FIG.
The outer ring is removed from the outer circumference of the cutter disk 72b of the child shield 72 in order to allow the cutter ring 73b of the child shield 72 to communicate with the cutter chamber 72a of the child shield 72. By doing so, the earth and sand excavated by the cutter ring 73b of the parent shield smoothly flows into the cutter chamber 72a of the child shield (in the figure,
An arrow A) is discharged by a drain pipe or a conveyor (not shown).

However, in the main excavator 71, FIG.
(A) As shown in FIG.
When the child shield 72 is separated from the parent shield 73 and excavated by itself, the surrounding ground (mainly the upper ground) passes through the cutter disk 72b of the child shield 72 and enters the cutter chamber 72a. (Arrow B in the figure).

Thus, in the excavators 61 and 71,
Even if the problem of excavating with the parent and child together is solved, the new problem described above occurs when excavating with the child shield alone.

[0017]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and has an inner shield in which an outer ring of a cutter disk is formed to have a substantially smaller diameter than a cone plate of a cutter chamber. As a result, a gap in the axial direction of the shield from the cutter ring side to the cutter chamber was secured outside the outer peripheral ring.
Therefore, since the rear of the cutter ring and the inner cutter chamber could be communicated without removing the outer ring and the cone plate of the inner shield, the excavated earth and sand by the cutter ring was removed from the inner cutter chamber without causing the ground around the shield to collapse. It became possible to send to.

[0018]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An excavator according to the present invention comprises an outer shield body having a cutter ring, and an inner shield body having a cutter disk and housed coaxially and nested in the outer shield body. A two-stage shield machine, wherein the inner shield body has a cutter chamber for taking excavated earth and sand behind the cutter disk, and an outer ring of a cutter disk of the inner shield covers an outer periphery of the cutter chamber. It is characterized in that it is formed substantially smaller in diameter than the shield cone plate.

In the excavator having such a configuration, a gap is formed between the outer peripheral ring of the cutter disk and the inner shield cone plate, which communicates in the front-rear direction. As a result, even when the outer shield main body and the inner shield main body are integrated, a passage of excavated earth and sand that passes through the cutter ring from the front of the excavator and passes through the gap to the cutter chamber is formed. Therefore, the earth and sand excavated by the cutter ring is taken into the cutter chamber, and can be easily discharged backward together with the earth and sand excavated by the cutter disk. Also, when the inner shield is dug alone, the periphery of the cutter disk is covered by the outer peripheral ring, and the periphery of the cutter chamber is covered by the inner shield cone plate. It does not fall into the inside of the cutter chamber. Here, the substantially small diameter means that, when the outer peripheral ring has a cylindrical shape, not only that the diameter is smaller than the diameter of the inner shield cone plate, but also that the outer peripheral ring has a tapered shape as described later. As a result, a step is formed between the inner shield cone plate and the outer ring, as in the case where the cutter ring is formed or a polygonal shape. It also means the shape of the outer ring.

Further, the outer peripheral ring of the cutter disk is formed in a tapered shape so as to be substantially reduced in diameter toward the rear of the inner shield main body. This is preferable in that the edges of the cutter disk and the cutter chamber can be closed when digging in the above.

Further, the outer peripheral ring of the cutter disk is formed to be substantially polygonal when viewed in the axial direction of the inner shield main body, as in the case of having the above-described outer peripheral ring. In addition to the function and effect, the production cost of the reinforcing material is lower than that of the above-mentioned ring-shaped material.

In the above shield excavator, the face of the outer shield body is configured so that its position is the same as or forward of the front end of the inner shield cone plate by a cutter ring. This is preferable in that excavated earth and sand is prevented from accumulating behind the cutter ring and compacting.

[0023]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view of an excavator according to the present invention.

FIG. 1 is a front view showing an embodiment of an excavator according to the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG.
FIG. 3A is a partial cross-sectional view illustrating the function of the child shield of the excavator shown in FIG. 1 when excavating alone, and FIG. 4) is a front view showing another embodiment of the excavator of the present invention, and FIG.
FIG. 5 is a sectional view taken along the line IV-IV of the excavator shown in FIG.
(A) is a front view showing still another embodiment of the excavator of the present invention, and FIG. 5 (b) is a cross-sectional view of the excavator of FIG. 5 (a) taken along line VV.

In FIGS. 1 and 2, reference numeral 1 denotes an excavator, and an outer shield body (hereinafter referred to as a parent shield as appropriate) 2
And an inner shield body (hereinafter referred to as “child shield” as appropriate) 3 housed coaxially and nested in the parent shield 2. The parent shield 2 and the child shield 3 are detachably connected by a connection device (not shown),
When only the child shield 3 is to be dug, the connecting device is removed to separate the two shields 2 and 3, and the child shield 3 is advanced while the parent shield 2 is left.

An annular cutter ring 4 is provided at the front end of the parent shield 2, and a circular cutter disk 5 is provided at the front end of the child shield 3. A cutter beam 7 having a plurality of cutter bits 6 fixedly mounted on the cutter ring 4 and the cutter disk 5, respectively.
8 are arranged radially. There is an open space 9 between the adjacent cutter beams, through which excavated earth flows into the cutter chamber 10 behind the cutter disk 5.

Then, inside the cutter disk 5,
The disk coupler 11 is built in. The disc coupler 11 is for connecting and separating the cutter ring 4 and the cutter disc 5. In this embodiment, three disk couplers 11 are provided on the circumference as shown in FIG. The disc coupler 11 is provided with a drive cylinder 11 mounted in the cutter beam 7 of the cutter disc 5.
The cutter ring 4 and the cutter disk 5 are connected by engaging the pin 11b with the boss 11c provided on the cutter ring 4 by a.

Reference numeral 12 in FIG. 2 denotes a fixing device for fixing the cutter ring 4 to the parent shield 2, and six fixing devices are provided on the circumference at substantially equal intervals. This fixing device 12
Is to lock the locking claw 12a of the cutter ring 4 with the locking claw 12b of the parent shield 2 after locking the locking claw 12a of the cutter ring 4 with the locking claw 12b of the parent shield 2. The two claws 12a, 12b are restrained in their locked state by the
It is fixed to.

The number of the disk couplers 11 is not limited to three, and the number of the fixing devices 12 is not limited to six, but may be increased or decreased according to the size of the excavator.

Reference numeral 13 denotes a drive motor for rotating and driving the cutter ring 4 and the cutter disk 5, and includes a reduction gear 14, a pinion 15, and a gear 16 coaxial with the shield.
The cutter disk 5 is rotated via the. When the cutter ring 4 is connected to the cutter disk 5, the cutter ring 4 also rotates integrally with the cutter disk 5.

Reference numeral 17 denotes a plurality of propulsion jacks arranged at substantially equal intervals on the circumference of the child shield 3. The propulsion jack 17 pushes the front end of the assembled segment to advance the child shield 2. The segments are assembled into a cylindrical shape by an unillustrated erector.

In this embodiment, the cutter chamber 1
An earth pressure type using a screw conveyor 18 is adopted as equipment for discharging the excavated earth and sand in the area 0. Of course, in the present invention, a system such as an open mechanical system using a belt conveyor or a muddy water system using a mud feeding pipe and a mud discharging pipe can be adopted in addition to the earth pressure type.

Reference numeral 19 denotes a bulkhead, which is a child shield 3
Is a closing member that separates the inside 3a of the main body from the cutter chamber 10, and prevents earth and sand or muddy water from flowing into the inside 3a of the main body.

Reference numeral 20 denotes an outer peripheral ring of the cutter disk, which is a short cylindrical member that covers substantially the outer periphery of the cutter disk 5. By arranging the outer ring 20,
The inflow of earth and sand from the surroundings into the cutter disk 5 is prevented. Reference numeral 21 denotes a cone plate portion that covers the outer periphery of the cutter chamber 10 of the child shield 3. In this embodiment, the cone plate portion 21 is formed by extending the skin plate 22 of the child shield 3 forward. The cone plate portion 21 prevents earth and sand from flowing into the cutter chamber 10 from the periphery thereof.

As shown in FIG. 2, an entrance packing 23 for sealing a narrow gap T between the parent shield 2 and the child shield 3 is provided over the entire circumference of the inner peripheral surface of the parent shield 2 in the circumferential direction. ing.

The front end face 24 of the parent shield 2 (also referred to as the face of the parent shield), that is, the portion corresponding to the rear end of the cutter ring 4 is closed.
The excavated earth and sand due to the above-mentioned method is prevented from flowing into the inside 2a of the main body of the parent shield 2.

The outer ring 2 of the child shield 3
0 has a smaller diameter than the cone plate portion 21. Accordingly, when the excavator 1 is viewed from the front, a gap S1 is formed between the outer peripheral ring 20 and the cone plate portion 21. With this configuration, the earth and sand excavated by the cutter ring 4 smoothly flows into the cutter chamber 10 through the gap S1 (arrow C) as shown in FIG. 3B without remaining in the cutter ring, It is discharged by the screw conveyor 18.

In FIG. 1, reference numeral 25 designates a copy cutter device for performing extra excavation when the child shield 3 excavates alone.

Next, as shown in FIG. 3 (a), when the child shield 3 is separated from the parent shield 2 and excavated by itself, the periphery of the child shield 3 is formed by the outer peripheral ring 20 and the cone plate portion 21. Ground is child shield 3
Of the cutter disk 5 and the cutter chamber 10 is prevented.

In the excavator 31 shown in FIG. 4, the outer peripheral ring 32 of the child shield 3 has a partially conical shape. That is, the cross section of the outer ring 32 is tapered so that the diameter thereof is reduced toward the rear of the shield. Therefore, as shown in FIG. 4 (b), a gap S2 from the cutter ring 4 to the cutter chamber 10 is formed, and the earth and sand do not stay in the cutter ring but pass through the gap S2 (arrow C) in the cutter chamber 10. , And is discharged by the screw conveyor 18.

The excavator 41 shown in FIG.
The outer peripheral ring 42 is not a cylindrical shape or a conical shape but a combination of flat plates. As shown in FIG. 5 (a), the excavator 41 is arranged so as to have a hexagonal shape when viewed from the front. I have. Therefore, as shown in FIG. 5A, a gap S is provided between the outer peripheral ring 42 and the cone plate portion 21.
3 is formed. Then, during excavation, the earth and sand smoothly flows into the cutter chamber 10 through the gap S3 (arrow C) as shown in FIG. 5B without remaining in the cutter ring, and is discharged by the screw conveyor 18. . Further, by arranging the outer peripheral ring 42 in a hexagonal shape in this manner, there is an effect that the manufacturing cost is lower than that of the ring-shaped outer peripheral rings 20 and 32 as a reinforcing material. In the present invention, the shape is not limited to a hexagonal shape, but may be a polygonal shape in which the gap can be formed.

Although not shown, an outer peripheral ring may be used in which the flat plate forming the polygon is directed rearward and is inclined toward the central axis of the shield.

In any one of the above-mentioned child shields 3, the surrounding ground is prevented from falling into the cutter chamber by the cone plate portion and the outer peripheral ring during the excavation alone.

[0044]

According to the present invention, when the outer shield main body and the inner shield main body are integrated, the earth and sand excavated by the cutter ring is taken into the cutter chamber, and together with the earth and sand excavated by the cutter disk. It can be easily discharged backward. Further, when the inner shield is excavated by itself, earth and sand around the inner shield does not fall into the cutter disk and the cutter chamber.

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of an excavator according to the present invention.

FIG. 2 is a sectional view taken along line II-II of the machine shown in FIG.

3A is a partial cross-sectional view illustrating a function of the child shield of the excavator of FIG. 1 at the time of single excavation, and FIG. 3B is a partial cross-sectional view illustrating a function at the time of parent-child integrated excavation.

FIG. 4A is a front view showing another embodiment of the excavator of the present invention, and FIG. 4B is a cross-sectional view of the excavator shown in FIG.

5 (a) is a front view showing still another embodiment of the excavator of the present invention, and FIG. 5 (b) is a sectional view taken along line VV of the excavator of FIG. 5 (a).

6A and 6B show an example of a conventional two-stage excavator, in which FIG. 6A is a partial cross-sectional view illustrating a function of a child shield when excavating alone, and FIG. It is a partial sectional view.

7A and 7B show another example of a conventional two-stage excavator, in which FIG. 7A is a partial cross-sectional view illustrating a function of the child shield when excavating alone, and FIG. It is a partial sectional view for explaining.

FIG. 8 shows still another example of the conventional two-stage excavator,
(A) is a partial cross-sectional view explaining the function of the child shield at the time of single excavation, and (b) is a partial cross-sectional view illustrating the function of the parent shield at the time of excavation.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Machine 2 ... Parent shield 3 ... Child shield 4 ... Cutter ring 5 ... Cutter disk 9 ... Space 10 ... Cutter chamber 11 ... Disk coupler 18 ..Screw conveyor 20 ・ ・ ・ Outer peripheral ring 21 ・ ・ ・ Cone plate part 22 ・ ・ ・ Skin plate 24 ・ ・ ・ Face face 25 ・ ・ ・ Copy cutter device 31 ・ ・ ・ Excavator 32 ・ ・ ・ Outer peripheral ring 41 ・..Drilling machine 42 ... Outer ring S1 ... Gap S2 ... Gap S3 ... Gap

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-3-132597 (JP, A) JP-A 8-189287 (JP, A) JP-A-5-10597 (JP, U) (58) Survey Field (Int.Cl. ⁶ , DB name) E21D 9/06 301 E21D 9/08

Claims (4)

(57) [Claims] 1. A two-stage shield machine comprising: an outer shield body having a cutter ring; and an inner shield body having a cutter disk and housed coaxially and nested in the outer shield body. The inner shield body has a cutter chamber for taking excavated earth and sand behind the cutter disk, and the outer ring of the inner shield cutter disk has a diameter substantially smaller than the inner shield cone plate covering the outer circumference of the cutter chamber. A two-stage shield machine characterized by being formed. 2. An outer peripheral ring of the cutter disk,
2. The two-stage shield machine according to claim 1, wherein the machine is formed in a tapered shape so that the diameter is substantially reduced toward the rear of the inner shield body. 3. An outer peripheral ring of the cutter disk,
3. The two-stage shield machine according to claim 1, wherein the inner shield body is formed to have a substantially polygonal shape when viewed in the axial direction of the inner shield body. 4. The face of the outer shield main body is configured to be located at the same position as or at the front of the front end of the inner shield cone plate.
A two-stage shield machine according to any one of the preceding claims.