JP2000257369A - Shield machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shield machine capable of excavating even a small- diametral tunnel and even a large-diametral tunnel only by, slight remodeling, to simplify the structure of the shield machine, to reduce manufacturing cost and remodeling cost, and to simply change over a tunnel diameter. SOLUTION: A drum member 3 has an internal rear-drum tail plate 6, an external rear-drum tail plate 5 externally fitted to the tail plate 6 concentrically at a space and a front drum 4, the shield machine is propelled under the state, in which front drum 4, the tail plate 5 and the tail plate 6 are mounted, and a segment 30 for a small-diametral tunnel is assembled on the internal surface side of the tail plate 6 under the state, in which the small-diametral tunnel is excavated, and the shield machine is propelled under the state, in which the tail plate 6 is removed, and a segment for a large-diametral tunnel is assembled on the internal surface side of the tail plate 5 under the state, in which the large-diametral tunnel is excavated.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield machine, and more particularly to a shield machine capable of excavating tunnels having different diameters and covering a segment, in which a small tunnel is excavated and a large tunnel is excavated. The present invention relates to a shield machine capable of being easily switched over in a state in which the shield machine is used.

[0002]

2. Description of the Related Art Shield tunneling machines are used for subways, water and sewage systems, tunnels for power cables and communication cables,
Shield tunnels (tunnels) such as, etc., the usual shield excavator, the front fuselage, the bent part, the rear trunk,
A cutter disk at the front end of the front body, a rotary drive mechanism for rotating and driving the cutter disk, for example 8 to 8 which are disposed on the inner peripheral side of the front body rear part, the bent part and the rear body front end part and are fixed to the rear body front end part; It has 20 shield jacks, bent jacks on the left and right sides, an earth removal facility for discharging excavated earth and sand, and an erector for lining a segment on the inner surface of the excavated tunnel.

[0003] According to this shield excavator, a cutter disk is rotated to excavate a cutting face while generating excavating thrust through segments covered with a plurality of shield jacks, and a predetermined length (for one ring) is obtained. ) Each time excavation, lining the segment on the inner surface of the tunnel with the erector device,
The tunnel is dug while repeating this.

[0004] Incidentally, in a sewer tunnel, in order to largely change the diameter of the tunnel in the middle of the tunnel, or to secure a space for arranging cable connecting devices and the like in a tunnel for a power cable or a communication cable.
In some cases, a large-diameter tunnel having a predetermined length in which the tunnel diameter is widened is formed in the middle of the tunnel. For example, Japanese Unexamined Patent Publication No. 6-58077 discloses a shield machine capable of increasing the diameter of a tunnel. The applicant of the present application has proposed a shield excavator that can be repeatedly remodeled into a reduced-diameter state in which a small-diameter tunnel is excavated and an expanded-diameter state in which a large-diameter tunnel having a larger diameter than a small-diameter tunnel is excavated (Japanese Patent Application No. Hei. 9-270535).

In the shield machine described in Japanese Patent Application Laid-Open No. 6-58077, a shaft is formed at a starting point where the diameter of the tunnel is widened, a small-diameter tunnel is machined to the position of the shaft, and then a shield machine is formed immediately below the shaft. A large-diameter front fuselage was added to cover the outer peripheral side of the front fuselage of the machine, and a large-diameter rear fuselage was attached in place of the small-diameter rear fuselage. Excavate a large diameter tunnel. In this shield machine, when excavating a large-diameter tunnel, an overcutter previously mounted on a cutter spoke of a cutter disk is extended.

[0006] In the shield excavator proposed by the present applicant, when switching to a large diameter tunnel during excavation of a small diameter tunnel, a small diameter shield excavator for excavating a small diameter tunnel at the starting end of the large diameter tunnel is used. Excavate a shaft with a diameter larger than the total length, convert the small-diameter shield excavator directly below the shaft into a large-diameter shield excavator that excavates a large-diameter tunnel, and excavate a large-diameter tunnel with the large-diameter shield excavator. .

At the time of the remodeling, the small-diameter rear body is cut off at the position of the dividing line, most of the small-diameter rear body is carried out to the ground, and then the upper divided body and the lower divided body of the large-diameter front trunk are separated. A large-diameter front body is assembled from the ground to cover the outside of the small-diameter front body, and the front body is made into a double structure. Carry in and assemble to make a large diameter rear trunk. In parallel with this, a second eccentric metal fitting for the large diameter tunnel is attached to each shield jack instead of the first eccentric metal fitting for the small diameter tunnel, and the cutter spokes of the cutter disk are added to change the state from the small diameter state to the large diameter state. To remodel. After the above modification, excavation of the large-diameter tunnel is started by this large-diameter shield excavator, and the large-diameter tunnel following the small-diameter tunnel is excavated.

[0008]

[Problems to be Solved by the Invention] JP-A-6-5807
The shield machine described in Japanese Patent Publication No. 7 is only for excavating a large-diameter tunnel of a predetermined length only once, and when switching to excavation of a small-diameter tunnel after excavation of a large-diameter tunnel, a large-diameter front trunk and a rear excavator are used. It is almost impossible to dig through the large tunnel afterwards, leaving the torso underground. If the large-diameter front and rear bodies are remanufactured, the large-diameter tunnel can be excavated again, but this is disadvantageous because the extra cost of manufacturing the large-diameter front and rear bodies is required.

In order to excavate a large-diameter tunnel and a small-diameter tunnel using the shield machine proposed by the present applicant, a large-diameter and small-diameter front trunk and a large-diameter and small-diameter rear trunk are required.
The number of structural members is large, the manufacturing cost is high, and the remodeling cost is high. Since the plurality of shield jacks are arranged at radial positions suitable for a small-diameter shield machine, the amount of eccentricity of the second eccentric metal fitting for the large-diameter tunnel is extremely larger than the amount of eccentricity of the first eccentric metal fitting. Become. Therefore, as a plurality of eccentric fittings corresponding to a plurality of shield jacks, a plurality of first and second eccentric fittings are provided.
Problems such as the necessity of the second eccentric metal fitting, the necessity of a large shield jack having a large rod diameter as each shield jack, and the shortening of its life due to the large eccentric load acting on the shield jack. is there.

An object of the present invention is to provide a shield excavator capable of excavating both a small-diameter tunnel and a large-diameter tunnel with a small modification, to simplify the structure of the shield excavator and reduce the manufacturing cost, This is to simplify the switching of the excavator according to the diameter of the tunnel.

[0011]

According to a first aspect of the present invention, there is provided a shield machine comprising: an excavator body; a body member covering an outer peripheral portion of the excavator body; a cutter disc; In a shield machine equipped with a plurality of shield jacks, the trunk member includes an inner rear trunk tail plate, an outer rear trunk tail plate concentrically fitted with an inner rear trunk tail plate at an interval, and Having an outer rear trunk tail plate and a front trunk member of the same diameter,
In a state in which a small-diameter tunnel corresponding to the inner rear trunk plate is excavated, a small-diameter tunnel segment is mounted on the inner surface side of the inner rear trunk tail plate by using an erector device while excavating with the trunk member mounted, and In the state of excavating a large-diameter tunnel having a larger diameter than the above, the inner rear body tail plate is detached from the body member and excavated, and a large-diameter tunnel segment is assembled on the inner surface side of the outer rear body tail plate. It is characterized by having done.

During tunnel excavation, excavation is performed while rotating a cutter disk by a driving means, and excavation is performed while generating excavation thrust by a plurality of shield jacks. When excavating a small-diameter tunnel, the excavation proceeds while the front body member, the inner rear trunk tail plate, and the outer rear trunk tail plate are provided, and the excavation is interrupted every time a predetermined length (for one ring) is excavated. Assemble the small-diameter tunnel segment in a ring shape on the inner surface side of the inner rear trunk plate with the device,
Almost in parallel with this, a backfill material such as mortar is filled between the ground and the small-diameter tunnel segment. When switching to the state of excavating the large diameter tunnel, the front body member and the outer rear body tail plate are not changed, and only the inner rear body tail plate is removed and carried out. In the state of excavating the large-diameter tunnel, a large-diameter tunnel segment is assembled in a ring shape on the inner surface side of the outer rear trunk tail plate by the erector device for each excavation of one ring, and almost in parallel with the ground. Fill backfill material between large diameter tunnel segments.

According to a second aspect of the present invention, there is provided a shield excavator according to the first aspect of the present invention, wherein a simultaneous back-filling injection device is provided between the inner rear trunk tail plate and the outer rear trunk tail plate when excavating the small diameter tunnel. It is characterized by the following. The annular space between the inner rear trunk plate and the outer rear trunk plate can be used effectively, and when assembling the segment for the small diameter tunnel, the simultaneous backfilling device interferes with the segment for the small diameter tunnel, the elector device, etc. Never do.

The shield machine according to a third aspect of the present invention is characterized in that, in the second aspect of the present invention, the simultaneous backfilling device is removed when switching to the state of excavating the large diameter tunnel. Since the simultaneous backfilling device is removed, the large-diameter tunnel segment can be mounted on the inner surface side of the outer rear trunk tail plate. When assembling the large-diameter tunnel segment, the backfill material is filled from the inner surface side of the large-diameter tunnel segment through an injection hole formed in the segment.

According to a fourth aspect of the present invention, there is provided a shield machine.
In any one of the third inventions, the mounting positions of the plurality of shield jacks in the tunnel radial direction are the same regardless of the size of the tunnel diameter. However, it is desirable that the mounting position in the radial direction of the tunnel is substantially at a position between the inner surface of the segment for the small diameter tunnel and the inner surface of the segment for the large diameter tunnel. The shield jacks can be used for both small-diameter tunnel excavation and large-diameter tunnel excavation while maintaining the radial installation positions of the plurality of shield jacks constant. Since it is not necessary to change the positions of the plurality of shield jacks, the load of remodeling the excavator due to the change in the tunnel diameter can be reduced, and the remodeling cost can be reduced.

According to a fifth aspect of the present invention, in the invention of the fourth aspect, the spreader is eccentrically connected to the output rod of each shield jack via an eccentric fitting, and the amount of eccentricity is the same regardless of the diameter of the tunnel. There is a common eccentric fitting for each eccentric fitting regardless of the diameter of the tunnel.Each eccentric fitting is maximally eccentric to the inside of the tunnel in the radial direction when excavating a small diameter tunnel. It is characterized in that it can be eccentric as far as possible outward in the radial direction of the tunnel.

As the eccentric fitting, the same eccentricity is used irrespective of the diameter of the tunnel, so a common eccentric fitting is applied. Therefore, it is sufficient to provide one kind of eccentric fitting, so that the manufacturing cost of the eccentric fitting is reduced. be able to. When excavating small diameter tunnels, each eccentric fitting is maximally eccentric to the inside of the tunnel radial direction, and when excavating large diameter tunnels, each eccentric fitting is maximally eccentric to the outside of the tunnel radial direction. After disconnecting the eccentric fitting from the spreader, the eccentric fitting may be rotated 180 degrees around the axis of the shield jack and connected to the spreader again.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. The shield machine according to the present embodiment is configured to be capable of being repeatedly remodeled into a state in which a small diameter tunnel is excavated (see FIGS. 2 to 4) and a state in which a large diameter tunnel is excavated (see FIGS. 5 to 7). I have. FIG. 1 shows a state in which a small-diameter tunnel A and a large-diameter tunnel B larger in diameter than the small-diameter tunnel A are excavated by the shield excavator. It is to be noted that the tunnel excavation direction is referred to as the front, and the left and right are referred to as the left and right toward the front.

FIGS. 2 to 4 show a shield excavator 1A for excavating a small-diameter tunnel A. The shield excavator 1A is composed of an excavator main body 2 and a body member for covering an outer peripheral portion of the excavator main body 2. 3 (which has a front trunk 4, an outer rear trunk tail plate 5, and an inner rear trunk tail plate 6), a cutter disk 7 rotatably provided at the front end of the excavator body 2, and a cutter disk 7 , A cutter driving mechanism 8 for rotating and driving, a ten shield jacks 9, an erector device 10, an earth discharging facility 11, and the like. In addition, front torso 4
Corresponds to the front trunk member.

As shown in FIGS. 2 and 3, the cutter disk 7 is provided with a plurality of cutter spokes 12 and a number of cutter bits 13 attached to the front end of the cutter spokes 12. Spoke 12
One of them is provided with a copy cutter device 14 for excavation. The cutter driving mechanism 8 is composed of a plurality of hydraulic motors 8a and the like, and is fixed to a front end of the excavator main body 2, that is, to a vertical partition wall 15 inside the body member 3, and drives the cutter disk 7 to rotate forward and reverse. In the center of the partition wall 15, a rotary joint or the like having a built-in oil passage for supplying oil to the copy cutter device 14 is provided.

As shown in FIG. 2, a ring web 16 is fixed to the inner peripheral surface of the rear end of the front body 4 and
The support brackets 17 are fixed to the front of the support bracket 6 at appropriate intervals in the circumferential direction. For example, ten shield jacks 9 are disposed at appropriate positions in the circumferential direction so as to penetrate the ring web 16 and be mounted rearward, and these shield jacks 9 are laid via spreaders 18 during excavation. The reaction force is applied to the front end of the completed segment to generate thrust of the shield machine 1A.

As shown in FIGS. 2 and 8, an eccentric fitting 19 is detachably bolted to the output rod 9 a of each shield jack 9, and a substantially elliptical spreader 18 is attached to an engaging portion 19 a of each eccentric fitting 19. Are eccentrically pin-connected so that the connection can be released. A common eccentric metal is used as each eccentric metal 19 regardless of the diameter of the tunnel. When the small-diameter tunnel A is excavated (see FIG. 8), the engaging portion 19a of each eccentric metal 19 is maximally inward in the tunnel radial direction. Limit (eccentricity δ)
When the large-diameter tunnel B is excavated (see FIG. 9), the engaging portion 19a of each eccentric metal fitting 19 is eccentric to the outermost side in the tunnel radial direction (eccentricity δ).

Each eccentric fitting 19 is fixed to the output rod 9a, but is rotatable around its axis together with the output rod 9a. When the eccentric fitting 19 is connected to the spreader 18, the eccentric fitting 19 is spread by the spreader 18. The rotation is restricted. When the eccentric direction of the eccentric fitting 19 is switched in order to switch the tunnel diameter, the eccentric direction can be switched by once disconnecting the connection between the eccentric fitting 19 and the spreader 18, and after the eccentric direction is switched, the eccentric fitting 19 is switched. May be connected to the spreader 18.

As shown in FIGS. 4 and 7, in each of the spreaders 18 having a substantially elliptical shape in a front view, one outer peripheral edge portion 18a has an inner rear body tail plate 6 as shown in FIG.
(See FIG. 4), and the other outer peripheral edge portion 18b is formed with the same curvature as the inner peripheral surface of the outer rear trunk tail plate 5 (see FIG. 7). Therefore, in this shield machine 1A, the engaging portion 19a of each eccentric metal 19 is maximally eccentric to the inside in the tunnel radial direction, and the eccentric metal 19 is regulated by the spreader 18 so as not to rotate. The peripheral portion 18a comes into sliding contact with the inner peripheral surface of the inner rear trunk tail plate 6.

As shown in FIG. 2 and FIG.
Reference numeral 0 includes an erector base frame 21, an erector main body 22, an erector turning motor 23, and the like. The erector base frame 21 is formed in a substantially cylindrical shape, and an annular engaging portion 21a protrudes from an outer peripheral portion thereof. A plurality of brackets 24 are fixed to the rear end of the ring web 16 at appropriate intervals in the circumferential direction. Each of the brackets 24 is pivotally mounted with an idle roller 26 rotatable around an axis parallel to the excavation direction. These rollers 2
6 support the engaging portion 21a, and
Is rotatable.

An endless chain 27 is attached to the inner peripheral front end of the erector base frame 21, and a motor support bracket 28 projecting from the inner surface of the front body 4 is provided with an erector turning motor 23. A proket 23a driven by 23 is engaged with the endless chain 27 so that the turning motor 23 can drive the erector base frame 21 to rotate forward and reverse. The erector main body 22 is fixed to the rear end face of the erector base frame 21 by bolts. Incidentally, 21
b is a balance weight.

As shown in FIG. 2, the front trunk 4 of the trunk 3
And the outer rear trunk plate 5 are formed to the same outer diameter,
The rear end of the front trunk 4 and the front end of the outer rear trunk tail plate 5 are welded. The inner rear trunk tail plate 6 has a smaller diameter than the outer rear trunk tail plate 5 and is fitted concentrically to the outer rear trunk tail plate 5 at an interval, and the front end of the inner rear trunk tail plate 6 is welded to the ring web 16. Are joined. In each shield jack 9, a notch (not shown) for preventing interference with the shield jack 9 is formed at the tip of the inner rear trunk plate 6. In addition, 6a is a tail grout seal. In the state where the small diameter tunnel is excavated, the simultaneous back-filling injection device 2 is provided between the outer rear trunk tail plate 5 and the inner rear trunk tail plate 6.
9 is provided so that a backing material (for example, mortar or the like) can be injected between the ground and the small-diameter tunnel segment 30.

FIGS. 5 to 7 show a shield excavator 1B for excavating a large-diameter tunnel B, which is a partially modified shield excavator 1A. Next, the shield machine 1B will be described, and the same members as those of the shield machine 1A will be assigned the same reference numerals and explanations thereof will be omitted as appropriate. As shown in FIG. 5, the shield machine 1B includes a machine 2 and
Body member 3 (this is a front body 4 and an outer rear body tail plate 5
), A cutter disk 7, a cutter driving mechanism 8, ten shield jacks 9, an erector device 10, an earth discharging facility 11, and the like. In this shield excavator 1B, the inner rear trunk tail plate 6 and the simultaneous backfilling device 29 are removed.

As shown in FIGS. 5, 7 and 9, in this shield excavator 1B, a spreader 18 is detachably connected to each shield jack 9 via an eccentric fitting 19 in an eccentric state. Are arranged so that the outer peripheral edge portion 18b of the outer slidable portion slides on the inner peripheral surface of the outer rear trunk tail plate 5, and each eccentric metal 19 is eccentric to the maximum inward in the radial direction of the tunnel.
8, the rotation of the eccentric fitting 19 is restricted. Although not shown, the large-diameter tunnel segment 35 is provided with a backing material injection hole through which a backing material is injected from the inside.

The operation of the shield machine 1A, 1B described above will be described. When excavating the small diameter tunnel A, excavation is performed by the shield excavator 1A. That is, both the inner rear trunk plate 6 and the simultaneous back-filling injection device 29 are provided, and the engagement portion 19a of the eccentric fitting 19 is connected to the spreader 18 in a state where the engagement portion 19a is eccentric to the maximum in the tunnel radial direction (eccentric amount δ). (See FIG. 8), the outer peripheral edge portion 18a of the spreader 18 is arranged to slide on the inner peripheral surface of the inner rear trunk tail plate 6, and in this state (see FIG. 4), the cutter driving mechanism 8 The disk 7 is rotated to excavate a face, and excavation is performed while generating a propulsive force by a plurality of shield jacks 9. At this time, a reaction force is applied to the front end of the covered small-diameter tunnel segment 30 by the spreader 18 connected to each shield jack 9 via the eccentric fitting 19, and a plurality of shield jacks 9 generate excavation thrust.

The small-diameter tunnel A is excavated, and the excavation is interrupted every time excavation of one ring of the segment is completed, and a backing material is injected from the simultaneous backing injection device 29, and
By 0, the small-diameter tunnel segment 30 for one ring is lined on the inner side of the inner rear trunk plate 6. At this time, the small-diameter tunnel segment 30 is assembled while supporting the soil water pressure load acting on the front surface of the shield machine 1A by a plurality of shield jacks 9 corresponding to locations other than the portion to be lining with the small-diameter tunnel segment 30. Then, the assembled segment 30 is pushed backward a small distance by the shield jack 9 and connected to the existing segment 30. Excavation is resumed after the assembly of the small-diameter tunnel segment 30 for one ring is completed. This is repeated in order, and the small diameter tunnel A is dug.

When switching to excavation of the large-diameter tunnel B during excavation of the small-diameter tunnel A, a suitable large shaft C is excavated at the starting position of the large-diameter tunnel B, and the shaft C
Right below the shield machine 1A and the shield machine 1
Remodel to B. In this case, the erector main body 22 of the erector device 10 is removed from the erector base frame 21 as necessary, each spreader 18 is separated from the eccentric metal fitting 19, the inner rear trunk plate 6 is blown off and separated from the ring web 16. It is carried out to the outside, and the simultaneous back-filling injection device 29 is also disassembled and carried out.

Next, as shown in FIG.
Is rotated 180 degrees around the axis of the shield jack 9 so that the engaging portion 19a is maximally eccentric to the outside in the tunnel radial direction, and the spreader 18 is similarly turned 180 degrees so that the outer peripheral edge 18b of the spreader 18 is After being arranged so as to slide on the inner peripheral surface of the outer rear trunk plate 5 (see FIG. 7), each spreader 18 is connected to the eccentric metal fitting 19. Further, the erector main body 22 is attached to the erector base frame 21 as needed.

After the above modification is completed, the shield machine 1B
Becomes operable, the excavation of the large-diameter tunnel B is started by the shield machine 1B, and the large-diameter tunnel B following the small-diameter tunnel A is almost similar to the excavation of the small-diameter tunnel A.
Is excavated. That is, the digging of the large-diameter tunnel is continued, and the digging is interrupted every time the digging of one ring of the segment is completed, and the digging is performed through the lining material injection hole between the large-diameter tunnel segment 35 and the ground. Material is injected, and the
As a result, the large diameter tunnel segment 35 for one ring is attached to the inner surface side of the outer rear trunk tail plate 5 in the same manner as described above. After the assembly of the segments 35 for one ring is completed, the excavation is resumed. This is repeated one after another, and the large-diameter tunnel B is dug.

When the large-diameter tunnel B is switched to the small-diameter tunnel A again after excavating the desired length, the large-diameter tunnel B
Is excavated at the end of the shaft, and the shield excavator 1B is connected to the shield excavator 1A immediately below the shaft C.
To remodel. Since the modification to the shield machine 1A is a modification for restoring the shield machine 1B, the modification can be easily carried out by the reverse procedure.

Here, the shield outer diameters of the shield excavators 1A and 1B are the same, and when excavating the small-diameter tunnel A, the excavation is performed with a diameter larger than the diameter required for the small-diameter tunnel A. The consumption of materials increases. In the case of the present embodiment, the outer diameter of the small-diameter tunnel segment 30 is, for example, 2750 mm, and the outer diameter of the large-diameter tunnel segment 35 is, for example, 2950 mm.
mm. When the dimensional difference between the two is not so large, the shield excavators 1A and 1B are applied,
The total excavation cost can be reduced even if the cost of backing material is added. That is, the shield machine 1A can be easily remodeled from 1A to 1B or vice versa, the structure is simple, the rebuilding period is short, and the rebuilding cost is low.

According to the shield excavators 1A and 1B described above, the front body 4 is commonly applied to excavation of both small-diameter and large-diameter tunnels.
Since it is not necessary to perform the remodeling, the remodeling time can be shortened and the remodeling cost can be reduced. Further, since only one kind of the front body 4 may be provided, the number of members of the front body 4 is reduced, and the manufacturing cost of the shield machine can be reduced. When excavating the small-diameter tunnel A, the excavation is carried out with the outer rear trunk tail plate 5 in addition to the inner rear trunk tail plate 6, and when the excavation of the small-diameter tunnel A is switched to the excavation of the large-diameter tunnel B, Since it is sufficient to remove the inner rear trunk plate 6, the time for remodeling at the time of changing the tunnel diameter can be shortened and the remodeling cost can be reduced.

Further, when excavating the small diameter tunnel A,
Since the outer rear body tail plate 5 is provided in addition to the inner rear body tail plate 6, the inner rear body tail plate 6 is provided.
Since the load condition of (1) is relaxed, the thickness can be reduced, the weight can be reduced, and the manufacturing cost can be reduced. In the state where the small-diameter tunnel A is excavated, the simultaneous back-filling device 29 is provided between the inner rear trunk tail plate 6 and the outer rear trunk tail plate 5, so that the inner rear trunk tail plate 6 and the outer rear trunk tail plate are provided. The simultaneous backfilling device 29 can be provided by effectively utilizing the annular space between the five, and interference between the simultaneous backfilling device 29 and the erector device 10 or the small diameter tunnel segment 30 can be prevented.

When switching to the state of excavating the large-diameter tunnel B, the simultaneous back-filling device 29 is removed, so that the large-diameter tunnel segment 35 can be assembled to the inner surface side of the outer rear trunk plate 5. . Since the mounting positions of the plurality of shield jacks 9 in the tunnel radial direction are the same regardless of the size of the tunnel diameter, there is no need to change the mounting positions of the plurality of shield jacks 9 when switching the tunnel diameter. Therefore, the structure of the excavator for switching the tunnel diameter can be simplified, and the production cost and the remodeling cost can be reduced.

As the plurality of eccentric fittings 19, the amount of eccentricity is the same irrespective of the size of the tunnel diameter, and a common eccentric fitting is applied. Therefore, only one type of eccentric fitting 19 is required. The manufacturing cost of the eccentric fitting 19 can be reduced. When the small-diameter tunnel A is excavated, each eccentric fitting 1
9 is maximally eccentric inward in the tunnel radial direction, and when excavating the large-diameter tunnel B, each eccentric metal 19 is maximally eccentric in the radially outer side of the tunnel, so that the eccentric amount of the eccentric metal 19 is not extremely increased. Since it can be used, the moment acting on the output rod of the shield jack 9 does not become so large, the diameter of the shield jack 9 can be reduced, and the manufacturing cost of the plurality of shield jacks 9 can be reduced.

Next, a modified embodiment in which the present embodiment is partially modified will be described. 1) The outer diameters of the small-diameter tunnel segment 30 and the large-diameter tunnel segment 35 are not limited to the above dimensions. Similarly, the difference between the outer diameters is not limited to 200 mm, and may be 200 mm or less, or 200 mm or more. 2) The inner rear trunk plate 6 is welded to the ring web 16, but may be detachably connected to members other than the ring web 16 by a joining method other than welding. 3) It is also possible to provide a center bending mechanism between the front trunk 4 and the outer rear trunk tail plate 5. In addition, various changes can be made to the above embodiment without departing from the spirit of the present invention.

[0042]

According to the first aspect of the present invention, the front body member is commonly applied to the excavation of both small-diameter and large-diameter tunnels, so that it is necessary to modify the front body member when changing the tunnel diameter. Since there is no remodeling, the remodeling time can be shortened and the remodeling cost can be reduced. Also, since only one type of front trunk member is required, the number of front trunk members is reduced, and the production cost of the excavator can be reduced. When excavating a small-diameter tunnel, excavate with the outer rear fuselage tail plate in addition to the inner rear trunk tail plate, and when switching from small-diameter tunnel excavation to large-diameter tunnel excavation, the inner rear trunk tail plate can be removed. ,
The time required for remodeling at the time of switching the tunnel diameter can be shortened, and the remodeling cost can be reduced. In addition, when excavating small diameter tunnels, the outer rear body tail plate is equipped in addition to the inner rear body tail plate, so the load condition of the inner rear body tail plate is eased, so it is made thinner and lighter and manufactured. Costs can be reduced.

According to the second aspect of the present invention, when excavating a small-diameter tunnel, the simultaneous back-filling device is provided between the inner rear trunk tail plate and the outer rear trunk tail plate. A simultaneous backfilling device can be provided by effectively utilizing the annular space between the outer rear trunk plate, and interference between the simultaneous backfilling device and the erector device or the small diameter tunnel segment can be prevented. The other effects are the same as those of the first aspect.

According to the third aspect of the present invention, when switching to the state of excavating the large-diameter tunnel, the simultaneous backfilling device is removed, so that the large-diameter tunnel segment is provided on the inner surface side of the outer rear trunk tail plate. Can be assembled. Other effects are the same as those of the second aspect.

According to the fourth aspect of the present invention, the mounting positions of the plurality of shield jacks in the tunnel radial direction are the same regardless of the size of the tunnel diameter. Since there is no need to change the mounting position, the structure of the excavator for switching the tunnel diameter can be simplified, and the production cost and the remodeling cost can be reduced. Other effects similar to those of any one of the first to third aspects are exhibited.

According to the fifth aspect of the present invention, a common eccentric fitting is applied to the plurality of eccentric fittings regardless of the diameter of the tunnel, so that only one type of eccentric fitting is required.
The manufacturing cost of a plurality of eccentric fittings can be reduced. When excavating a small-diameter tunnel, each eccentric fitting is maximally eccentric to the inside in the tunnel radial direction.When excavating a large-diameter tunnel, each eccentric fitting is maximally eccentric to the outside in the tunnel radial direction. Since it can be used without increasing the size, the moment acting on the output rod of the shield jack is not so large, the diameter of the shield jack can be reduced, and the manufacturing cost of a plurality of shield jacks can be reduced. The other effects are the same as those of the fourth aspect.

[Brief description of the drawings]

FIG. 1 is a sectional view of a tunnel excavated by a shield machine according to an embodiment of the present invention.

FIG. 2 is a longitudinal sectional view of the shield machine in a state where a small diameter tunnel is excavated.

FIG. 3 is a schematic front view of the shield machine shown in FIG. 2;

4 is a vertical sectional view of the shield machine shown in FIG. 2 (the left half is a sectional view taken along line IVa-IVa in FIG. 2, and the right half is a sectional view taken along line IVb-IVb in FIG. 2).

FIG. 5 is a longitudinal sectional view of the shield machine in a state where a large diameter tunnel is excavated.

FIG. 6 is a schematic front view of the shield machine shown in FIG. 5;

7 is a longitudinal sectional view of the shield machine shown in FIG. 5 (the left half is a sectional view taken along the line VIIa-VIIa in FIG. 5, and the right half is a VIIb-VIIb in FIG. 5).
FIG.

FIG. 8 is an enlarged sectional view of a main part showing a positional relationship between a shield jack, an eccentric metal fitting, a spreader and the like when excavating a small diameter tunnel.

FIG. 9 is an enlarged view of a main part showing a positional relationship between a shield jack, an eccentric metal fitting, a spreader and the like when excavating a large diameter tunnel.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1A, 1B Shield machine 2 Machine body 3 Body member 4 Front trunk 5 Outer rear trunk tail plate 6 Inner rear trunk tail plate 7 Cutter disk 8 Cutter drive mechanism 9 Shield jack 9a Output rod 10 Elector unit 18 Spreader 19 Eccentric fitting 29 Simultaneous backfilling device 30 Segment for small diameter tunnel 35 Segment for large diameter tunnel A Small diameter tunnel B Large diameter tunnel

Claims (5)

[Claims] 1. A shield machine comprising: an excavator main body; a body member covering an outer surface of the excavator main body; a cutter disk; driving means for rotating and driving the cutter disk; and a plurality of shield jacks. The body member includes an inner rear body tail plate, an outer rear body tail plate concentrically fitted to the inner rear body tail plate at an interval, and a front body member having the same diameter as the outer rear body tail plate. In a state in which a small-diameter tunnel corresponding to the inner rear trunk tail plate is excavated, a small-diameter tunnel segment is assembled on the inner surface side of the inner rear trunk tail plate using an erector device while excavating with the trunk member mounted. In a state where a large diameter tunnel having a larger diameter than a small diameter tunnel is excavated, the outer rear trunk tail is excavated with the inner rear trunk plate removed from the trunk member. Shield machine, characterized by being configured to assemble the segment for large diameter tunnel on the inner surface side of the rate. 2. The shield machine according to claim 1, further comprising a simultaneous back-filling device between the inner rear body tail plate and the outer rear body tail plate when excavating a small-diameter tunnel. 3. The shield machine according to claim 2, wherein the simultaneous backfilling device is removed when switching to a state where a large diameter tunnel is excavated. 4. The shield machine according to claim 1, wherein the plurality of shield jacks are mounted at the same position regardless of the diameter of the tunnel. 5. The spreader is eccentrically connected to the output rod of each shield jack via an eccentric fitting, and the amount of eccentricity is the same regardless of the size of the tunnel diameter, and each eccentric fitting is independent of the size of the tunnel diameter. A common eccentric fitting is applied, and when excavating a small diameter tunnel, each eccentric fitting is maximally eccentric to the inside in the tunnel radial direction, and when excavating a large diameter tunnel, each eccentric fitting is maximally eccentric to the outside in the tunnel radial direction. The shield machine according to claim 4, wherein the shield machine is used.