JPH08158785A - Tunnel excavation shield machine with different diameter - Google Patents

Abstract

PURPOSE: To eliminate subsidiary methods such as ground freezing, chemical grouting, etc., enable the execution of cut-off work in a tunnel joint with a mechanical construction and to make it possible to simplify the construction of a shield machine in comparison with a previously applied shield machine. CONSTITUTION: A cutter disc 32 of a small diameter shield machine 3 and a cutter chamber 33 including a rotary driving device 36 thereof are arranged in a vertical direction along a skinplate 31a through a slide jack 37 in a slidable manner. An outside diameter of a cutter disc main body 13 equipped with an over cutter 14 of a large diameter shield machine 1 is slightly smaller than an inside diameter of the skinplate 31a. A joint ring 22 is projected forward to a bulk head 18 of the large diameter shield machine 1, and a cutter disc 12 is capable of moving to a large diameter shield machine main body 11 so that a rotational center position of the cutter disc 32 corresponds with the rotational center position of the cutter disc 32.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield machine for excavating tunnels of different diameters, which is used for excavating tunnels having different diameters from both sides and joining them in the ground.

[0002]

2. Description of the Related Art In recent years, railways, roads, etc. have been installed in the strata,
Demand for so-called subways, underpasses, etc. will increase, and on the other hand, there will be new water supply and sewerage, electricity, etc.
Demand for new telephone lines is also increasing. Especially in urban development, the number of new construction works such as sewers, electricity, and telephone lines is rapidly increasing. As a machine for excavating tunnels to install these in the stratum, shield machines (also called shield excavators) Is often used. The tunnel formation by this shield machine has a limit to the excavable distance in the shield machine, so multiple vertical shafts are provided at the junctions of the excavable distance, and continuous tunnels are excavated by the shield machine between the vertical shafts. Is forming.

Even when a tunnel machine is excavated by the above-mentioned type of shield machine, for example, in sewer construction, a so-called branch pipe having a small diameter is provided on the upstream side and a so-called main pipe having a large diameter is provided on the downstream side. In order to form a continuous sewer by connecting them, or for the construction of electricity, telephone lines, etc., install a large diameter so-called main pipe at the supply source and a small diameter so-called branch pipe at the demand destination to connect these By doing so, a continuous wiring path may be formed. Therefore, the tunnel for providing the sewer or the wiring path as described above needs to have different diameters, that is, so-called different diameter tunnels.
Although it is around m to 150 cm, there may be a difference in diameter more than that.

However, since it is necessary to provide a plurality of vertical shafts at the joint point as described above, when it is attempted to secure a site for a joint point provided at a distance that can be excavated by a shield machine or a joint point having a different diameter, the site is to be secured. It takes a large amount of money to secure it, and in addition, it takes a very long construction period and cost to construct a vertical shaft at the site and excavate with each shield machine. In addition, when a tunnel is provided on the seabed, if the upper part of the junction is underwater, land reclamation will be performed to form a land, and the shaft will be provided on the land.
It requires a very long construction period and a large amount of cost. Therefore, an underground joining method has been proposed as a method for forming a tunnel in a short construction period without requiring many vertical shafts.

As a prior art relating to this underground joining method, there is an invention described in Japanese Patent Laid-Open No. 63-47499. In this invention, two shield machines having the same diameter are opposed to each other toward the tunnel junction. In this way, the tunnels are joined by excavating and facing each other at the joints, injecting the solidifying agent in the vicinity of the joints of both shield machines, and then dismantling the cutter disk etc. to join the tunnels with the same diameter. It can only be applied when

Further, there is an invention described in Japanese Patent Laid-Open No. 5-248170 as another method of joining shield machines. This invention also joins two shield machines of the same diameter, and is related to this application. It is impossible to join shield machines with widely different diameters to which the invention is directed.

Further, as a conventional technique of the underground joining method for tunnels having different diameters, there is an invention described in Japanese Patent Publication No. 6-6865. According to the present invention, two shield machines of a large diameter and a small diameter are moved so that a moving outer shell provided in front of the large diameter shield machine at a docking point is located on the outer circumference of the small diameter shield machine. The shield machine is dismantled after it is solidified by freezing or injecting a chemical solution between the outer shell of the small-diameter shield machine.

[0008] A prior patent application (Japanese Patent Application No. 6-
No. 167116), a shield machine body that is relatively movable in the axial direction of the skin plate is provided in the small-diameter shield machine, and a tube seal is provided inside the tip end portion of the skin plate. A water blocking means for sealing between the rear surface and the shield machine main body is provided, and a sealing surface having an outer diameter which is smaller than the inner diameter of the skin plate of the front small-diameter shield machine in the axial direction from the front surface of the cutter disk and has a substantially identical outer diameter. There is an invention of a structure in which a circular joint portion is eccentrically provided so as to be recessed.

[0009]

However, in the underground joining method for the tunnels with different diameters described in the above-mentioned publication, it is very difficult to project the moving outer shell forward in a place where the ground is hard. In addition, because it is necessary to freeze the joint and improve the ground so that groundwater does not pass through by injecting a chemical solution, a large-scale auxiliary construction method is required,
It requires a large construction cost and a long construction period. In addition, it is necessary to freeze a vast area or improve the ground, but if it freezes, there is a possibility that frozen soil will be expanded during freezing and ground subsidence during thawing.On the other hand, when improving the ground Requires long-term drug solution infusion. Furthermore, when sealing the joints only by freezing, the frozen soil is thawed due to the melting and heat insulation of the dismantling section that occurs during the dismantling work of the shield machine after freezing, causing water leakage, which makes it difficult to manage the frozen soil during the dismantling work. is there. Therefore, according to the above-mentioned underground joining method, it is extremely difficult to join the excavated different diameter tunnels to each other underground.

Further, in the underground joining device according to the above-mentioned prior application, at the time of underground joining, it is necessary to seal the two mechanical joints at the front and rear with a cutter disk of a large-diameter shield machine in an annular shape to stop water. Yes, the structure of the shield machine becomes complicated.

The present invention has been made in view of the above points, and does not require an auxiliary construction method such as freezing of the ground or injection of a chemical solution, and can reliably stop the water at the tunnel junction portion by a mechanical structure. It is an object of the present invention to provide a shield machine for excavating a different-diameter tunnel whose structure is simpler than that of the previous application.

[0012]

Means for Solving the Problems In order to achieve the above object, a shield machine for excavating a different diameter tunnel according to the present invention is a) starting excavation from both sides of a tunnel using a small diameter shield machine and a large diameter shield machine. In the shield machine for excavating different diameter tunnels that are to be bonded underground, b) slide the cutter chamber of the small-diameter shield machine and the cutter chamber part including the rotation drive device in the front-rear direction along the annular skin plate on the outer periphery thereof. It is movably arranged and provided with a slide jack for sliding the cutter chamber, c).
The large-diameter shield machine is provided with an overcutter that can be retracted radially outward from the outer peripheral edge of the circular cutter disk body, and d) the outer diameter of the cutter disk body is slightly smaller than the inner diameter of the skin plate. E) a bulkhead of the large-diameter shield machine is provided with a joining ring capable of fitting the inner peripheral surface of the skin plate in a forward direction, and f) the cutter disk has a rotation center position larger than that of the large-diameter shield machine. It is configured to be movable between a position corresponding to the central axis of the diameter shield machine main body and a position corresponding to the rotation center position of the cutter disk of the small diameter shield machine.

Further, as described in claim 2, a) a shield machine for excavating different diameter tunnels, in which excavation is started from both sides of a tunnel by using a small-diameter shield machine and a large-diameter shield machine to join underground, b ') At the tip of the outer peripheral surface of the annular skin plate of the small diameter shield machine, a slide ring plate is slidably arranged in the front-rear direction, and a slide jack for sliding the slide ring plate is provided. The diameter shield machine is equipped with an over-cutter that can be projected and retracted radially outward from the outer peripheral edge of the circular cutter disc body, and d) the outer diameter of the cutter disc body,
Formed slightly smaller than the inner diameter of the slide ring plate, e) a bulkhead of the large-diameter shield machine, and a joint ring capable of fitting the inner peripheral surface of the slide ring plate is projected forward, f) the The cutter disc may be configured to be movable between a position where its rotation center position coincides with the center axis of the large-diameter shield machine body and a position where it coincides with the rotation center position of the cutter disk of the small-diameter shield machine. .

As described in claim 3, g) a tube seal capable of bulging due to fluid pressure may be provided on the inner peripheral surface of the tip portion of the skin plate of the small diameter shield machine.

As described in claim 4, h) a tube seal capable of bulging by fluid pressure may be provided on the inner peripheral surface of the front end portion of the slide ring plate of the small diameter shield machine.

According to the fifth aspect, i) a freezing pipe for freezing the ground can be arranged along the peripheral surface of the joining ring.

[0017]

According to the shield machine for excavating different-diameter tunnels having the above-mentioned structure, the cutter disk of the large-diameter shield machine is rotated outwardly by projecting the over-cutter outward in the radial direction. When the excavation work is started, the excavation work of the small diameter tunnel is started by rotating the cutter disk of the small diameter shield machine in opposition. And with each shield machine reaching the junction point of both tunnels, after pulling the over cutter of the cutter disk of the large diameter shield machine into the cutter disk body, the center of rotation of the cutter disk of the large diameter shield machine Move it so that it matches the center of rotation of the cutter disk of the small-diameter shield machine. In this state,
The cutter chamber of the small-diameter shield machine is slid along the skin plate with a slide jack, retracted, and drawn into the shield machine body. Then, the small-diameter shield machine is advanced by a shield jack or the like, and the tip of the skin plate is fitted over the outer peripheral surface of the joining ring of the bulkhead beyond the periphery of the cutter disk of the large-diameter shield machine. As a result, the large-diameter shield machine and the small-diameter shield machine are mechanically joined, and at the same time, the large-diameter tunnel and the small-diameter tunnel are in communication with each other.

According to the shield machine for excavating tunnels of different diameters having the above-mentioned structure, the large diameter of the shield machine reaches the joining point of both tunnels in the same manner as the shield machine of the above-mentioned claim 1. Move the cutter disk of the shield machine so that the center of rotation is aligned with the cutter disk of the small-diameter shield machine. In this state, slide the slide ring plate on the outer peripheral surface of the skin plate of the small diameter shield machine,
The slide jack is projected forward, and the tip end thereof is fitted onto the outer peripheral surface of the joining ring of the bulkhead beyond the circumference of the cutter disk of the large-diameter shield machine. As a result, the large-diameter shield machine and the small-diameter shield machine are mechanically joined, and at the same time, the large-diameter tunnel and the small-diameter tunnel are in communication with each other.

According to another aspect of the shield machine of the present invention, the tube seal provided on the inner circumference of the skin plate tip portion is fluid pressured with the skin plate tip portion of the small diameter shield machine fitted on the joining ring of the large diameter shield machine. By bulging, the joints between the two are surely sealed, so that water and the like from the joints of the shield machine are prevented.

In the shield machine according to the fourth aspect, the tube seal provided on the inner circumference of the slide ring plate tip portion is expanded in a state where the slide ring plate tip portion of the small diameter shield machine is fitted on the joining ring of the large diameter shield machine. By letting it out, the joint between the two is surely sealed,
Water is prevented from entering between the joints of the shield machine.

In the shield machine according to the fifth aspect, the refrigerant is introduced into the freezing pipe provided on the peripheral surface of the joining ring of the large-diameter shield machine so that the tip portion of the skin plate or slide ring plate and the joining ring are separated from each other. The earth and sand will freeze and exert a sealing effect.

[0022]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a shield machine for excavating a different diameter tunnel according to the present invention will be described below with reference to the drawings.

FIG. 1 shows a normal excavation work state of a large-diameter shield machine out of two shield machines for excavating different-diameter tunnels according to this embodiment. FIG. 1 (a) is a lateral central sectional view. ,
1B is a half-arrow view taken along the line AA in FIG. 1A with the right half omitted, and FIG. 1C is a half sectional view taken along the line BB in FIG. 1A.
Fig. 2 (a) is a lateral center sectional view of two shield machines for excavating different diameter tunnels in the underground joint state, and Fig. 2 (b) is a half section in the AA direction of Fig. 2 (a) with the right half omitted. FIG. 2C is a half sectional view taken along the line BB of FIG. 2A.

As shown in FIGS. 1 and 2, the shield machine (digging machine) of this example comprises a large-diameter shield machine 1 and a small-diameter shield machine 3. The large-diameter shield machine 1 has a circular cutter disk 1 at the tip of the shield machine body 11, which is circular when viewed from the front.
2 is provided. The cutter disk 12 includes a plurality of bit frames 13a extending radially from the center and a disk body 13 having a large number of cutter bits 13b fixed along the bit frames 13a, and FIG.
The over cutter 14 is arranged so as to project radially outward from the outer periphery of the tip end of each bit frame 13a.
Consists of A plurality of cutter bits 14a are fixed to the front surface of the overcutter 14 in the radial direction, as shown in FIG.
The over cutter 14 is the bit frame 13a like
With these cutter bits 14 retracted inside
a is exposed to the front through an elongated opening 13c formed at the tip of the bit frame 13a.

The cutter disk 12 is rotatably supported by a support frame 16 via a bearing device 15, and the speed reducer 17a and the drive device 17 are also supported by the support frame 16. The support frame 16 is movably arranged upward in this example in a U-shaped frame 18a provided in the central portion of the bulkhead 18 of the shield machine body 11, and is fixed by a fixing bolt 19a during normal excavation work. 1 (c) and is suspended by a support bolt 19 suspended from the upper end frame of the U-shaped frame 18a as shown in FIG. 1 (c). With this structure, the cutter disk 12 is moved upward by removing the fixing bolt 19a and rotating the support bolt 19 in one direction to tighten it. That is, during normal excavation work, the center of rotation of the cutter disk 12 is located at the position that coincides with the central axis of the shield machine body 11 as shown in FIG. 1 (a), but at the time of underground joining, as shown in FIG. 2 (a). In addition, the rotation center of the cutter disk 12 moves to a position eccentric upward from the central axis of the shield machine main body 11 and is fixed by the fixing bolt 19a,
It coincides with the rotation center position of the cutter disk of the small diameter shield machine 3. The intrusion of earth and sand or muddy water from the face of the face is prevented by the seal rings 48a and 48b provided on the flange 48.

In this example, an earth pressure type shield machine is used as the large-diameter shield machine 1, and it faces the inside of the cutter chamber 20 formed between the cutter disk 12 and the bulkhead 18. The front end of the screw conveyor 21 inclined downward from the rear to the front is continuously provided. A skin plate (also referred to as a shield) 11 of the shield machine main body 11 in order to prevent interference with the overcutter 14 extending in the radial direction of the cutter disk 12.
A slight gap is formed between the a and the tip. A ring-shaped joining ring 22 is provided on the bulkhead 18 so as to project forward, centering on a rotation center position when the cutter disk 12 is moved upward. The outer peripheral surface of the joining ring 22 constitutes a kind of sealing surface when joined to the small diameter shield machine 3.

In FIG. 1A, reference numeral 23 is a shield jack, 24 is an erector device, 25 is a perfect circle holding device, and S
Is a segment piece.

As shown in FIG. 2, the main body 31 of the small-diameter shield machine 3 has a skin plate (shield) whose inner diameter is slightly larger than the outer diameter of the cutter disk 12 with the overcutter 14 retracted, that is, the disk body 13.
31a. At the tip of the skin plate 31a, a cutter chamber portion 33 having a circular cutter disk 32 as viewed from the front, in which the side over cutter 32c is drawn into the main body of the cutter disk 32, is slidably arranged in the front-rear direction. Has been done.

Incidentally, here, the cutter chamber portion 33
Is a connecting beam 32a, a ring body 32b, a side over cutter 32c, a bulkhead 34, a drive device 36, a slewing bearing 36a, a rear end support body mixed in a cylindrical fixing base 35 including a cutter disk 32 and a rotation drive device thereof. 39, the pipe 41, and the pipe 42 as a whole. The cutter disk 32 is integrally fixed to the connecting beam 32a and the ring body 32b on the rear surface, is rotatably supported by the slewing bearing 36a, and is a drive unit mounted on the rear surface of the cylindrical fixing base 35 via the slewing bearing 36a. The cutter disk 32 is rotated by 36. A slide jack 37 for moving the cutter chamber 33 in the front-back direction
Are provided between the skin plate 31a and the frame 31b fixed to the rear portion of the skin plate 31a, and the cutter chamber portion 33 is moved in the front-rear direction by the expansion / contraction operation thereof. A frame 31c is fixedly installed at an intermediate portion in the skin plate 31a, and the shield jack 3 is directed rearward from the frame 31c.
8 are provided. Further, the spacer 4 is provided between the frame 31c and the rear end support 39 of the cutter chamber 33.
0 can be detachably inserted, and the cutter chamber 33 includes a slide jack 37 and a spacer 4.
0 holds the excavation work position with respect to the shield machine main body 31.

In this example, a muddy water type shield machine is used as the small diameter shield machine 3, and a pipe 41 for introducing muddy water is used.
And a discharge pipe 42 are connected to the bulkhead 34 while facing the inside of the cutter chamber 35.
In addition, the cutter chamber portion 33 is provided in each of the pipes 41 and 42.
In order to allow the movement of the pipe, for example, an expandable pipe (not shown) having a double pipe structure is interposed. Note that FIG.
Reference numeral 43 in the figure is an elector device.

Regarding the underground joining operation by the shield machine for excavating the different diameter tunnel of the present embodiment configured as described above,
A description will be given based on FIGS. 3 and 4. 3 (a) to 4
(b) is a lateral center sectional view for sequentially explaining the operation (procedure) of the underground joint.

As shown in FIG. 3A, the large-diameter shield machine 1
The cutter disk 12 is rotated in a state where the over-cutter 14 is projected outward in the radial direction to continue the excavation work of the large-diameter tunnel to the joining position.
On the other hand, facing this, the cutter disk 32 of the small diameter shield machine 3 is rotated to continue the excavation work of the small diameter tunnel to the joining position. In the case of sewers, generally, an upstream tunnel and a downstream tunnel are
Join so that the upper ends of the vertical center lines are aligned.

As shown in FIG. 3B, the over cutter 1 of the cutter disk 12 of the large-diameter shield machine 1 in a state where the shield machines 1 and 3 reach the joining positions of both tunnels.
4 into the cutter disk body 13. Then, by removing the plurality of fixing bolts 19a (see FIG. 1 and FIG. 2) and rotating and tightening the plurality of support bolts 19, the cutter disk 12 is moved upward together with the support frame 16, and the rotation center of the cutter disk 12 is rotated. Is aligned with the center of rotation of the cutter disk 32 of the small diameter shield machine 3.

As shown in FIG. 4A, the small-diameter shield machine 3
After removing the spacer 40, the slide jack 37 is contracted to retract the cutter chamber 33 until the rear end support 39 contacts the intermediate frame 31c, and is retracted into the skin plate 31a.
During this time, the shield jack 23 is contracted to assemble the segment piece S.

As shown in FIG. 4B, the shield machine 3 is moved forward by pressing the rear end of the shield jack 23 against the assembled piece S to extend it. As shown in FIG. 3 (a), the cutter disk 3 is previously prepared.
Since the tunnel is excavated to the front surface of the cutter disk 12 of the large-diameter shield machine 1 by 2, the small-diameter shield machine 3 moves forward smoothly. Then, the tip of the skin plate 31a of the small-diameter shield machine 3 crosses over the cutter disk 12 of the large-diameter shield machine 1 and is fitted onto the outer peripheral surface of the joining ring 22, so that the large-diameter shield machine 1 and the small-diameter shield machine 1 3 and 3 are mechanically joined, and at the same time, the tunnels of the small diameter shield machine 3 and the large diameter shield machine 1 are in communication. In addition, if a cleaning nozzle (not shown) is provided on the outer peripheral side base of the protruding joining ring 22 of the large-diameter shield machine 1 and the outer peripheral surface of the joining ring 22 is cleaned at the time of joining, the skin plate 31 a The sealing property between the tip portion and the joining ring 22 is improved.

FIGS. 5 and 6 show another embodiment of the shield machine for excavating different diameter tunnels according to the present invention. FIG. 5 (a) shows that the small diameter shield machine and the large diameter shield machine are dug to the joining position. Fig. 5 (b) is a side central cross-sectional view showing a state in which a small-diameter shield machine and a large-diameter shield machine are joined, and Fig. 6 is an enlargement of the mechanical joining portion in Fig. 5 (b). FIG.

The shield machine of the present embodiment is different from the above embodiment in the following points. That is, as shown in FIG. 5, the slide ring plate 45 is slidably arranged in the front-rear direction at the tip of the outer peripheral surface of the skin plate 31a of the small-diameter shield machine 3.
5 is slid by the slide jack 46. The inner diameter of the slide ring plate 45 is slightly larger than the outer diameter of the cutter disc body 13 of the large-diameter shield machine 1, and the cutter disc 3 of the small-diameter shield machine 3 is slightly larger.
It is formed larger than the outer diameter of 2.

Further, as shown in FIG. 6, an annular groove 45a is formed at the tip of the inner peripheral surface of the slide ring plate 45, and a rubber tube seal 47 is formed which swells when a fluid pressure is introduced. I am wearing it. This tube seal 4
7 contracts in the groove 45a when the fluid pressure is discharged. As will be described later in a joining operation, since the slide ring plate 45 is advanced to join the joining ring 22 of the large-diameter shield machine 1 at the time of joining, the cutter chamber portion 33 is fixed to the shield machine body 31 and can be moved. Not like that. Therefore, there is no slide jack 37 for sliding the cutter chamber 33, and the spacer 40 is not used. In addition,
Reference numeral 47a in FIG. 6 is a fluid passage.

On the other hand, the joining ring 22 of the large-diameter shield machine 1
As shown in FIG. 6, the outer diameter is smaller than the inner diameter of the slide ring plate 45, and the tube seal 47 adheres to the outer peripheral surface of the joining ring 22 in a state where the tube seal 47 is swollen by the fluid pressure. An annular groove 22c is formed at the base end portion of the inner peripheral surface of the joining ring 22, and in this example, the freezing tubes 26 are arranged in parallel in three rows in this groove 22c. The freezing pipe 26 is connected to a cooling medium source (not shown) installed in the large-diameter shield machine body 11 so that the cooling medium can be circulated to the freezing pipe 26 via a circulation pump (not shown). There is. As a result, the water content in the sand existing in the gap between the tip of the slide ring plate 45 and the outer peripheral surface of the joining ring 22 can be frozen, and the gap can be completely sealed. Other configurations are the same as those of the shield machine of the above-described embodiment, and therefore the common parts are generally omitted in FIG. 5, and some of the common parts are illustrated by using the same reference numerals.

The underground joining operation by the shield machine for excavating the different diameter tunnel according to the second embodiment having the above-mentioned structure is shown in FIG.
It will be described based on.

With the shield machines 1 and 3 reaching the joining positions of both tunnels, the over cutter 14 of the cutter disk 12 of the large-diameter shield machine 1 is pulled into the cutter disk body 13. Then, the fixing bolt 19a
Is removed and the support bolt 19 is rotated and tightened to move the cutter disk 12 upward together with the support frame 16 so that the rotation center of the cutter disk 12 coincides with the rotation center of the cutter disk 32 of the small diameter shield machine 3. The operation up to this point is common to the above-described embodiment (FIG. 5 (a)).

In the shield machine of the present example, as shown in FIG. 5B, instead of advancing the small-diameter shield machine 3 at the joining position, the slide jack 46 is extended to move the slide ring plate 45 to the large-diameter shield machine. The large-diameter shield machine 1 and the small-diameter shield machine 3 are mechanically joined by passing over the cutter disk 12 of the machine 1 and fitting on the outer peripheral surface of the joining ring 22. After the joining, the tube seal 47 at the tip of the slide ring plate 45 is brought into close contact with the outer peripheral surface of the joining ring 22 in a state where the tube seal 47 is swollen by the fluid pressure, and at the same time, the cooling medium is circulated in the freezing pipe 26 to slide. It is possible to freeze water contained in the sand existing in the gap between the tip of the ring plate 45 and the outer peripheral surface of the joining ring 22 and completely seal the water.

Although two embodiments of the shield machine of the present invention have been shown above, the shield machine of the present invention can be implemented as follows.

(A) A muddy water shield machine is used as the large-diameter shield machine 1, and an earth pressure type shield machine 3 is used as the small-diameter shield machine 3.

(B) In the first embodiment, the tube seal 47 provided on the slide ring plate 45 of the second embodiment is attached to the tip of the skin plate 31a.

(C) In the first embodiment, the freezing tube 26 provided on the joining ring 22 of the second embodiment is attached to the inner peripheral surface or the outer peripheral surface of the joining ring 22.

(D) The moving range of the cutter disk 12 of the large-diameter shield machine 1 is the reference position where the center of rotation of the cutter disk 12 coincides with the central axis of the shield machine body 11,
It is a position where the center of rotation of the cutter disk 12 coincides with the position of the center of rotation of the cutter disk 32 of the small-diameter shield machine 3 facing each other. In the above two embodiments, the cutter disk 12 only needs to be moved in the vertical direction. The position is adjusted by rotating a plurality of support bolts 19 arranged in the vertical direction. However, when it is necessary to move not only in the vertical direction but also in the vertical plane including the horizontal direction, support bolts are arranged in the vertical direction and the horizontal direction, and the support frame 16 of the cutter disk 12 is slidably guided. A guide member is provided and a hydraulic cylinder is equipped in the moving direction.

[0048]

As is apparent from the above description,
The shield machine for excavating the different diameter tunnel according to the present invention has the following effects.

(1) The shield machine according to claims 1 and 2 does not require an auxiliary construction method such as freezing of the ground or injection of a chemical solution, and can reliably stop the water at the tunnel junction by a mechanical structure. Since the joining work is easy and the working time is drastically shortened, and the mechanical joining portion is only required at one place, the structure of the shield machine is considerably simplified as compared with that of the prior application.

(2) In the shield machine according to claim 2, the operation at the time of joining is simpler than that of the shield machine according to claim 1.

(3) In the shield machine according to claims 3 and 4, the tube seal at the tip of the skin plate or the slide ring plate is bulged to ensure a tight seal between the joints of the two and shield. It is possible to prevent water from entering between machine joints.

(4) In the shield machine according to the fifth aspect, by introducing a refrigerant into the freezing pipe, the sand or the like between the tip of the skin plate or the slide ring plate and the joining ring is frozen to seal the gap. It is possible to prevent water from entering between the joints of the shield machine.

[Brief description of drawings]

FIG. 1 shows a normal excavation work state of a large-diameter shield machine of two shield machines for different-diameter tunnel excavation according to an embodiment of the different-diameter tunnel excavation shield machine of the present invention,
1 (a) is a lateral central sectional view, FIG. 1 (b) is a half arrow view taken along the line AA of FIG. 1 (a) with the right half omitted, and FIG. 1 (c) is FIG. 1 (a).
3 is a half cross-sectional view taken along line BB of FIG.

2 (a) is a lateral center sectional view of two shield machines for excavating different diameter tunnels in the underground joint state, and FIG. 2 (b) is a right half of FIG. 2 (a). -A direction half arrow view, same figure
2C is a half cross-sectional view taken along the line BB of FIG.

3 (a) and 3 (b) are lateral central cross-sectional views for sequentially explaining the operation (procedure) of underground bonding.

FIG. 4 (a) and FIG. 4 (b) are lateral central cross-sectional views for sequentially explaining the operation (procedure) of underground bonding.

FIG. 5 shows another embodiment of the shield machine for excavating a different diameter tunnel of the present invention, and FIG. 5 (a) is a side view showing a state in which the small diameter shield machine and the large diameter shield machine are advanced to the joining position. A central sectional view, FIG. 5B is a lateral central sectional view showing a state where the small diameter shield machine and the large diameter shield machine are joined.

FIG. 6 is an enlarged cross-sectional view of the mechanical joint portion of FIG. 5 (b).

[Explanation of symbols]

 1 Large-diameter shield machine 3 Small-diameter shield machine 11/31 Shield machine body 12/32 Cutter disc 13 Disc body 14 Overcutter 15 Bearing device 16 Support frame 17/36 Drive device 18/34 Bulkhead 19 Support bolt 19a Fixing bolt 22 Joining Ring 26 Freezing tube 31a Skin plate 3 33 Cutter chamber 37/46 Slide jack 40 Spacer 45 Slide ring plate 47 Tube seal

Claims (5)

[Claims] 1. A shield machine for excavating different diameter tunnels, which starts excavation from both sides of a tunnel by using a small-diameter shield machine and a large-diameter shield machine and joins underground, a cutter disk of the small-diameter shield machine, and a rotation drive device thereof. A cutter chamber portion including a slidably arranged in the front-rear direction along the outer peripheral annular skin plate, and provided with a slide jack for sliding the cutter chamber portion, the large-diameter shield machine, A circular cutter disk main body is provided with an overcutter that can project and retract radially outward from the outer peripheral edge portion, and the outer diameter of the cutter disk body is formed to be slightly smaller than the inner diameter of the skin plate. On the bulkhead, a joining ring capable of fitting the inner peripheral surface of the skin plate is projected forwardly, The disk is configured to be movable between a position where its rotation center position coincides with the center axis of the large-diameter shield machine body and a position where it coincides with the rotation center position of the cutter disk of the small-diameter shield machine. A shield machine for excavating different diameter tunnels. 2. A shield machine for tunnel excavation of different diameter, which starts excavation from both sides of a tunnel by using a small-diameter shield machine and a large-diameter shield machine and joins underground. A slide ring plate is slidably arranged in the front-rear direction at the tip portion, and a slide jack for sliding the slide ring plate is provided. In addition to having an overcutter that can project and retract radially outward, the outer diameter of the cutter disk body is formed slightly smaller than the inner diameter of the slide ring plate, and the slide ring plate is attached to the bulkhead of the large-diameter shield machine. A joining ring that can fit the inner peripheral surface of the For excavating different-diameter tunnels, characterized in that the position is movable between a position corresponding to the central axis of the large-diameter shield machine body and a position corresponding to the rotation center position of the cutter disk of the small-diameter shield machine. Shield machine. 3. The shield machine for different diameter tunnel excavation according to claim 1, wherein a tube seal capable of bulging due to fluid pressure is provided on the inner peripheral surface of the tip portion of the skin plate of the small diameter shield machine. 4. The shield machine for tunnel excavation of different diameter according to claim 2, wherein a tube seal capable of bulging by fluid pressure is provided on the inner peripheral surface of the tip portion of the slide ring plate of the small diameter shield machine. 5. The shield machine for excavating a different diameter tunnel according to claim 1, wherein a freezing pipe for freezing the ground is arranged along the peripheral surface of the joining ring.