JP2000213279A - Shield machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a shield machine improved in the degree of freedom for setting the shape of an elliptical shield shaft, simplified in the constitution, reduced in the manufacturing cost, preventing generation of un-excavated area to be projected inward of a tunnel. SOLUTION: This shield machine 1 for excavating an elliptical shield shaft of approximately elliptical section comprises a cutter disk 3, a pair of planetary cutters 4 provided on its front part, a rotation mechanism for integratedly rotating these components and rotating a pair of planetary cutters 4, a pair of oscillation cutters 6 arranged on the right and left sides of the cutter disk 3, and a pair of oscillation mechanisms for oscillating the oscillation cutters 6. A center part of the elliptical shield shaft is excavated in an approximately square shape by the cutter disk 3 and a pair of planetary cutters 4, and the right and left parts of the center part are excavated by a pair of oscillation cutters.

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 for excavating an elliptical shield pit having a substantially elliptical cross section.

[0002]

2. Description of the Related Art Shield tunneling machines are widely used to construct various shield tunnels (water and sewage tunnels, subway tunnels, underground tunnels, communication cable tunnels, tunnels for communal trenches, etc.) using a shield method. Has been provided. Of these shield tunnels, especially in subway tunnel stations and underground tunnels, elliptical shield tunnels with an almost elliptical cross section are widely used in order to maximize the tunnel width in order to make effective use of the tunnel space. Have been.

Various shield machines have been proposed as shield machines for excavating the elliptical shield shaft. For example, an elliptical shield tunnel can be excavated by attaching a cutter disk in a normal shield excavator in a forwardly inclined state (or a backwardly inclined state in the opposite direction) and digging. In this case, the structure of the shield machine becomes complicated, and it is difficult to excavate a tunnel having a large diameter.

On the other hand, conventionally, a so-called triple shield excavator equipped with a pair of small-diameter sub-cutter disks on both the left and right sides of a large-diameter main cutter disk has also been put to practical use.
According to the triple shield excavator, the elliptical shield pit can be excavated by digging while rotating the three cutter discs, respectively. An unexcavated region that protrudes considerably inside the tunnel remains near the four boundary portions, and the outer peripheral shape of the tunnel does not become a smooth elliptical shape.

On the other hand, as a shield machine capable of excavating a shield shaft having an arbitrary cross-sectional shape, an oscillating shield machine has been proposed and put into practical use. In this swing type shield machine, a tunnel having a rectangular cross section can be excavated, for example, by swinging a rectangular cutter disk, so that an elliptical shield well is excavated by employing an elliptical cutter disk. be able to. In addition, as a form of the swing drive, swing (circular motion) like a crank operation, reciprocal swing by reciprocating rotation drive, and the like are applied.

Japanese Patent Application Laid-Open No. Hei 10-77779 discloses an outer shell member (body member) having an elliptical shape in a front view, a main cutter disk which is driven to rotate, and a slightly rearward shift of the main cutter disk to the left and right sides. A shield machine having a pair of secondary cutter discs mounted is described. In this shield machine, in order to excavate four places near the boundary between the main cutter disk and the pair of sub cutter disks, the main cutter disk includes:
A pair of copy cutters is provided, one copy cutter is provided for each sub-cutter disk, and these copy cutters are each driven to advance by a hydraulic cylinder.

[0007]

When the triple shield excavator is applied, an unexcavated area which protrudes considerably inside the tunnel remains near four boundary portions between the main cutter disk and the sub cutter disk. Since the outer peripheral shape of the tunnel does not become a smooth elliptical shape, it is difficult to increase the utilization rate of the space in the tunnel. Moreover, a large steel segment of special shape must be applied to cover the inner surface of the unexcavated area, so that the tunnel construction cost is high. It is not practical to excavate most of the shield pit with an oscillating shield machine because it is difficult to increase the excavation speed of the oscillating shield machine.

In the shield machine described in Japanese Patent Application Laid-Open No. H10-77779, four excavations near the boundary between a main cutter disk and a pair of sub-cutter disks are required.
When precisely controlling the drive of one copy cutter, it is necessary to precisely control the advance stroke of the hydraulic cylinder, so that the drive control system becomes complicated and expensive. Also, with this shield machine, the radius of the sub-cutter disk cannot be increased beyond the distance from the axis of the main cutter disk to the axis of the sub-cutter disk, so the elliptical cross section of the tunnel cannot be freely set, Since it is difficult to make the amount of advance of the copy cutter too large, the elliptical shape cannot be set freely.

It is an object of the present invention to increase the degree of freedom in setting the shape of the elliptical shield pit, to simplify the configuration and to reduce the production cost, and to prevent the occurrence of an unexcavated area projecting inside the tunnel. It is an object of the present invention to provide a shield machine capable of accomplishing the above.

[0010]

According to a first aspect of the present invention, there is provided a shield machine which excavates while advancing an elliptical shield pit having a substantially elliptical cross section, wherein a cutter disk provided at a front end of the shield machine is provided. A pair of planetary cutters provided on a front portion of the cutter disk, and a rotational drive unit for integrally driving the cutter disk and the pair of planetary cutters and rotating the pair of planetary cutters; It is characterized by comprising a pair of swing cutters arranged on both left and right sides or upper and lower sides of a cutter disk, and a pair of swing driving means for respectively swinging these swing cutters.

When excavating an elliptical shield pit, the cutter disk and a pair of planetary cutters are integrally rotated by a rotary driving means while applying a reaction force to the reinforced segment by a plurality of shield jacks. The pair of planetary cutters are rotated on their own axis, and the pair of oscillating cutters are respectively oscillated by a pair of oscillating driving means in parallel with the rotation. It is excavated circularly by a cutter disk. If the rotational speed ratio between the cutter disk and the planetary cutter is set to, for example, 1: 2 or 1: 4, four corners are excavated by the pair of planetary cutters, and therefore, the cutter disk and the pair of planetary cutters substantially excavate. It can be excavated in a square shape.

The left and right sides or the upper and lower sides of the cutter disk are excavated by the pair of swing cutters. If the shape of the pair of rocking cutters and the rocking drive form are appropriately set, an almost elliptical shape is formed by the cutter disk, the pair of planetary cutters, and the pair of rocking cutters as described above. Drill shield pits.

According to a second aspect of the present invention, there is provided the shield machine according to the first aspect, wherein the pair of swing cutters are disposed so as to be shifted rearward with respect to a cutter disk. . Interference between the cutter disk and the planetary cutter and the swing cutter can be reliably prevented, and the excavation area of the cutter disc and the swing cutter can be partially overlapped.

According to a third aspect of the present invention, there is provided the shield machine according to the first or second aspect of the invention, wherein the swing cutter has a sector shape having an opening angle larger than 180 degrees in a front view. is there. The shape of the swinging cutter can be set so as not to largely overlap with the digging area by the cutter disk and the planetary cutter, and the lateral width of the digging cross section can be made larger.

According to a fourth aspect of the present invention, there is provided the shield machine according to the third aspect, wherein the swing driving means is configured to swing the swing cutter back and forth by a predetermined angle around its support shaft. It is assumed that. Therefore, the structure of the swing driving means can be simplified.

According to a fifth aspect of the present invention, there is provided a shield machine.
4. The invention according to claim 4, wherein a rotation speed ratio between the planetary cutter and the cutter disk is 4: 1. That is, the planetary cutter makes four rotations while the cutter disk makes one rotation. Here, the shape to be excavated by the cutter disk and the pair of planetary cutters can be freely set according to the rotation speed ratio and the contour shape of the planetary cutter in a front view, but the rotation speed ratio is set to 4: 1 as described above. Then, it can excavate in a substantially square cross section.

According to a sixth aspect of the present invention, there is provided a shield excavator for excavating an elliptical shield pit having a substantially elliptical cross section, comprising: a cutter disk provided at a front end of the shield excavator; A drive means, a pair of swing cutters disposed on both left and right sides or upper and lower sides of the cutter disk, and a pair of swing drive means for respectively swinging these swing cutters. Is what you do.

When excavating the elliptical shield pit, the cutter disk is rotated by the rotary driving means, and in parallel with this, a pair of rocking cutters are respectively rocked by the pair of rocking drive means. The central portion of the elliptical shield pit can be excavated by a cutter disk, and the left and right sides or the upper and lower sides of the central portion can be excavated by a pair of swing cutters. Excavation can be performed by a pair of oscillating cutters without leaving an unexcavated area at the boundary between the cutter disk and the oscillating cutter at these boundary portions.

According to a seventh aspect of the present invention, in the shield machine according to the sixth aspect, the swing driving means is configured to swing the swing cutter back and forth by a predetermined angle around its support shaft,
A pair of projecting portions for excavating areas left uncut by the cutter disk are integrally provided at both ends of each swing cutter. The cutter disk can be rotated to excavate in a circular shape, and each rocking cutter is reciprocally rocked by a predetermined angle around its support shaft by each rocking drive means, and provided integrally at both ends of each rocking cutter. With the pair of overhangs, the areas left uncut by the cutter disk can be respectively excavated.

[0020] In a shield machine according to an eighth aspect of the present invention, in the invention according to the sixth aspect, the swing driving means is configured to swing the swing cutter reciprocally around a support shaft by a predetermined angle,
The present invention is characterized in that there are provided four drum cutters for excavating areas left unexcavated by the cutter disk and the pair of swing cutters. In this way, the four drum cutters can reliably excavate the area left unexcavated by the cutter disk and the pair of swing cutters.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A shield machine according to an embodiment of the present invention will be described below. This shield machine is a shield machine that excavates while advancing an elliptical shield pit having a substantially elliptical cross section. In the description below, the front, rear, left, and right directions in the excavation direction are referred to as front, rear, left, and right, respectively.

As shown in FIGS. 1 to 3, a shield machine 1 has a body member 2 having an elliptical cross-sectional shape, and a circular cutter viewed from the front, which is disposed at a front end of the shield machine 1. A disc 3; a pair of planetary cutters 4 provided on the front surface of the cutter disc 3;
A rotation drive mechanism 5 for integrally rotating the pair of planetary cutters 4 and rotating the pair of planetary cutters 4;
A pair of oscillating cutters 6 arranged on both right and left sides of the cutter disk 3, a pair of oscillating drive mechanisms 7 for respectively oscillating the oscillating cutters 6, and a partition wall structure 8 for defining a chamber And so on.

Although not shown, the shield excavator 1 has a plurality of shield jacks for generating thrust for excavation and a segment for assembling segments on the inner surface of the elliptical shield well in addition to the above-described configuration. It has an erector and an earth removal facility (or a sludge facility) for discharging the excavated earth and sand.

As shown in FIG. 1, the partition wall structure 8 includes a central wall 8a, an inner cylindrical wall 8b, an annular wall 8c, an outer cylindrical wall 8d, and an annular wall 8.
e, etc., and defines a chamber for storing excavated earth and sand at the front end of the excavator. As shown in FIGS. 1 and 2, the cutter disk 3 includes a disk body including a plurality of cutter spokes 3a radially arranged in a front view, and a center extending rearward from the center of the disk body to the central wall 8a. A member 3c, an annular drum member 12,
It has four cylindrical connecting members 13 for connecting the drum member 12 to the disk body. A number of cutter bits are fixed to the front surface of each of the cutter spokes 3a of the disk body with bolts (or welding).

The annular drum member 12 has an inner cylindrical wall 8b.
And is rotatably mounted via a bearing between the outer cylinder wall 8d and
It is in a sealed state via a sealing member. A center support shaft 3b is rotatably supported in the center member 3c. A hydraulic passage and other fluid passages are formed in the center support shaft 3b as needed. Each of the pair of planetary cutters 4 has a leaf shape in a front view, and each of the pair of planetary cutters 4 has its phase angle set to be point-symmetric with respect to the center of the cutter disk 3. I have. A plurality of cutter bits are also provided on the outer periphery of each planetary cutter 4 with bolts (or welding).

As shown in FIGS. 1 and 3, the rotation driving mechanism 5
Are a plurality of hydraulic drive motors 9 mounted on the annular wall 8c.
(An electric motor may be used), a pinion gear 10 fixed to the motor shaft of the hydraulic drive motor 9, a ring gear 11 meshed with the pinion gear 10 and driven to rotate by the hydraulic drive motor 9, and a pair of planetary shafts. 1
5 and a planetary gear mechanism 16. Since the ring gear 11 is integrally connected to the drum member 12, the cutter disc 3 and the pair of planetary cutters 4 are rotationally driven around the center support shaft 3 b by the plurality of hydraulic motors via the ring gear 11. be able to.

As shown in FIGS. 1 and 3, a planetary shaft 15 connected to the center of rotation of each of the planetary cutters 4 is inserted into a corresponding cylindrical connecting member 13, and is provided on the rear side of the drum member 12. Extending to The planetary gear mechanism 16 is for rotating (rotating) the pair of planetary cutters 4 with the driving force of a plurality of hydraulic motors 9 (or electric motors). The planetary gear mechanism 16 includes a pair of planetary shafts 15.
A pair of planetary gears 17 integrally fixed to the rear end side of the
And an idle gear 18 meshed with each of these planetary gears 17 and a sun gear 19 commonly meshed with these idle gears 18. The sun gear 19 is fixedly provided on the outer periphery of the inner cylindrical wall 8b.

As shown in FIGS. 1 to 3, the pinion gear 10 is driven by a plurality of hydraulic drive motors 9 (or electric motors).
Rotates, the drum member 12 rotates via the ring gear 11, and the cutter disk 3 rotates via the plurality of tubular connecting members 13. In parallel with the rotation of the cutter disk 3, a pair of idle gears 18 rotates with respect to the sun gear 19, and the pair of idle gears 18 rotates a pair of planetary gears 17 via the planetary shaft 15. The pair of planetary cutters 4 respectively rotate.

In the planetary gear mechanism 16, the idle gear 18, the planetary gear 17, and the sun gear 1 are arranged such that the rotation speed ratio between the planetary cutter 4 and the cutter disk 3 is 4: 1.
Nine teeth are set in advance. Therefore, each planetary cutter 4 rotates four times in the direction opposite to the rotation direction of the cutter disk 3 while the cutter disk 3 makes one rotation.

As shown in FIGS. 1 and 2, the pair of swinging cutters 6 are formed in a fan shape having an opening angle larger than 180 degrees when viewed from the front, and are shifted rearward with respect to the cutter disk 3. It is arranged. Each oscillating cutter 6 has a plurality of cutter spokes, and a plurality of cutter bits are attached to front portions of the plurality of cutter spokes by bolt fixing (or welding). A pair of swing drive mechanisms 7 for reciprocatingly rotating these pair of swing cutters 6 around their support shafts and swinging them will be described.

As shown in FIGS. 1 and 3, support frames 20 project inward from both left and right ends of the body member 2, respectively.
Attached to. Each swing drive mechanism 7 includes a horizontal support shaft 21 that is connected to the center of rotation of the swing cutter 6 and that is separated in the front-rear direction, a support member 22 that is mounted on the support shaft 21 and rotatably supports the support shaft 21, , A bearing 22a, and a rotation drive unit 23 that drives the support shaft 21 to rotate.

In the rotation drive unit 23, a connecting member 23b is connected to the rear end of the support shaft 21.
A piston rod of a hydraulic cylinder 23a is connected to both ends of the hydraulic cylinder 23b.
The support shaft 21 is reciprocally oscillated via the connecting member 23b by alternately driving the piston rod a to advance and reciprocately rotate the oscillating cutter 6 about the support shaft 21 by a predetermined small angle. The cutter 6 is configured to be driven to swing.

Next, the operation of the shield machine 1 described above will be described. When excavating the elliptical shield pit while moving forward, the pinion gear 10 is rotated by the hydraulic drive motors 9 (or electric motors) of the rotary drive mechanism 5 while the reaction force is applied to the reinforced segment by the shield jacks. Then, the drum member 12 is rotated via the ring gear 11, and the cutter disk 3 is rotationally driven via the plurality of tubular connecting members 13. Cutter disk 3
In parallel with the rotation of, a pair of planetary gears 17 is rotationally driven via a planetary gear mechanism 16, and the central portion of the elliptical shield pit is excavated to have a substantially square cross section.

When the pair of planetary cutters 4 revolves as described above while revolving, the planetary cutters 4 move as shown in the movement trajectory of FIG. 4 on the upper left and right sides
One corner is reliably excavated by the pair of planetary cutters 4.
The behavior of the planetary cutter 4 will be described later in detail in a first modification. This cutter disk 3
In parallel with the rotation of the shaft, the pair of pivot shafts 21 are reciprocally rotated by a predetermined angle by the pair of rocking drive mechanisms 7, and the pair of rocking cutters 6 are reciprocally rocked by the predetermined angle. Excavate both right and left sides of the.

Since a pair of planetary cutters 4 is provided and the pair of planetary cutters 4 is driven to rotate at a rotation speed four times as high as that of the cutter disk 3, the central portion of the elliptical shield shaft is excavated in a substantially square shape. The structure for the excavation can be simplified. Then, by appropriately changing the shape of the planetary cutter 4, the cross-sectional shape that can be excavated by the cutter disk 3 and the pair of planetary cutters 4 can be changed quite freely, so that the flatness of the elliptical shield well can be changed, Excellent in nature.

Each of the pair of swinging cutters 6 is formed in a sector shape having an opening angle larger than 180 degrees when viewed from the front, so that the swinging cutters 6 swing so as not to largely overlap with the excavation area formed by the cutter disk 3 and the planetary cutter 4. The shape of the cutter 6 can be set, and the structure can be reduced. Also,
Since the swing drive mechanism 7 is configured to swing the swing cutter 6 reciprocally around the support shaft 21 by a predetermined angle, the structure of the swing drive mechanism 7 can be simplified, and the manufacturing cost of the shield machine 1 can be reduced. Can be reduced.

The shape of the pair of swing cutters 6 can be set almost freely, and the shape of the pair of planetary cutters 4 can be set variously, so that the degree of freedom in setting the shape of the elliptical shield shaft is remarkably increased. Can be increased. In addition, since there is no unexcavated area projecting to the inside of the tunnel at the outer periphery of the tunnel, the utilization rate of the space inside the tunnel can be increased, and there is no need to cover with a special steel segment. Work costs can be reduced. In addition, since both the rotary drive mechanism 5 and the pair of swing drive mechanisms 7 can have a relatively simple configuration, their manufacturing costs can be reduced.

Next, a modified embodiment in which the shield machine is partially modified will be described. 1] Modification 1 ... See FIGS. 5 to 7) As shown in FIG. 5, the pair of swing cutters 25 of the shield machine 1A are formed in a semicircular shape having an opening angle of 180 degrees when viewed from the front. It is arranged to be shifted rearward with respect to the cutter disk 3. In addition, similar to the above embodiment,
A pair of planetary cutters 4, a rotary drive mechanism 5, a pair of swing drive mechanisms 7, and the like are provided. The swing cutter 25
The oscillating cutter 6 is reciprocally oscillated by a predetermined small angle about a support shaft at the center thereof, similarly to the oscillating cutter 6. In the shield machine 1A, since the pivot of the swing cutter 25 is closer to the center of the cutter disk 3 than in the shield machine 1, the degree of flattening of the ellipse of the elliptical shield shaft is reduced.

The rotation speed ratio between the planetary cutter 4 and the cutter disk 3 is set to 4: 1 as in the above embodiment, but the shape of the planetary cutter 4 is slightly changed. Here, the principle of digging into a substantially square cross section by the planetary cutter 4 will be described with reference to FIGS. A substantially square outer shape excavated by the pair of planetary cutters 4 is defined as a rectangle h. When the planetary cutter 4 rotates while revolving, the cross section of the rectangle h can be excavated by drawing a trajectory inscribed in the rectangle h. That is, the planetary cutter 4
When it rotates four times while revolving once, the contour shape of the planetary cutter 4 is determined so that the locus of the farthest point from the orbital center O of the planetary cutter 4 draws a rectangle h.

Now, assuming that the revolution locus of the rotation center Ob of the planetary cutter 4 is a circle K, points m1, m2,.
Indicates the position of the rotation center Ob of the planetary cutter 4 at each angle θ when the planetary cutter 4 is rotated by an angle θ (θ = 15 °). Points P1, P2, ... on rectangle h
Is a point at which a straight line connecting each point m1, m2,... On the circle K and the center of revolution O intersects the rectangle h.

Here, when the rotation center Ob of the planetary cutter 4 is at the position of the point m1, the radius of the planetary cutter 4 is set to the point m1 on the circle K and the rectangle to make the planetary cutter 4 inscribe the rectangle h. It must be a straight line length n1 connecting the point P1 on h. When the planetary cutter 4 revolves from the position of the point m1 by the angle θ and moves to the position of the point m2, in order for the planetary cutter 4 to be inscribed in the rectangle h, the radius of the planetary cutter 4 must be a point on the circle K. It must be a straight line length n2 connecting m2 and point P2 on rectangle h.

Similarly, when the planetary cutter 4 moves to the position of the point m3, the radius of the planetary cutter 4 is not the straight line length n3 connecting the point m3 on the circle K and the point P3 on the rectangle h. No. On the other hand, the planetary cutter 4 rotates at an angle of 4θ while revolving at an angle of θ. Therefore, as described above, the contour shape of the planetary cutter 4 is determined by sequentially determining the radius length of the planetary cutter 4, and thus the contour shape of the planetary cutter 4 becomes a leaf shape. As described above, the rotation speed ratio between the planetary cutter 4 and the cutter disk 3 is set to 4: 1 and the outline shape of the planetary cutter 4 in a front view is formed into a leaf shape as described above, so that a pair of planetary cutters is formed. In particular, the corners having a substantially square cross section can be excavated by the cutter 4.

2] Modification 2—See FIG. 8 As shown in FIG. 8, the shield machine 1B has a cutter disk 26 provided at the front end thereof, and a rotary drive mechanism for driving the cutter disk 26 to rotate. A pair of oscillating cutters 27 disposed on both left and right sides of the cutter disk 26;
It has a pair of rocking drive mechanisms and four drum cutters 28 for excavating areas left undigged by the cutter disk 26 and the pair of rocking cutters 27, respectively. These four drum cutters 28 are arranged to be shifted slightly backward from the pair of swing cutters 27, and are also provided with a rotation drive mechanism for rotating each swing cutter 27. The cutter disk 26 includes a plurality of cutter spokes 26 a radially arranged in a front view, and includes a pair of swing cutters 27.
Also includes a plurality of cutter spokes 27a. The swing cutter 27 is also driven to swing back and forth by a predetermined angle about the center support shaft.

When excavating an elliptical shield mine while moving forward by the shield machine 1B, the cutter disk 26 is rotated by a rotary drive mechanism while a reaction force is applied to the reinforced segment by a plurality of shield jacks, A pair of rocking cutters 27 is provided by a pair of rocking drive mechanisms.
Is reciprocated by a predetermined angle, and in parallel with this, the four drum cutters 28 are rotated by a rotation driving mechanism (not shown). Center the center of the elliptical shield shaft with the cutter disk 26
, And the center part of the left and right sides is excavated by a pair of oscillating cutters 27, and the area left unexcavated by the cutter disk 26 and the pair of oscillating cutters 27 is subjected to four drum cutters 28. Excavate. Therefore, it is possible to excavate a substantially elliptical shield tunnel whose outer peripheral surface is smoothly continuous.

3] Modification 3—See FIG. 9 As shown in FIG. 9, in the shield machine 1C, areas left uncut by the cutter discs 26 are excavated at both ends of each swing cutter 27, respectively. A pair of overhangs 27b
Are provided integrally. Each oscillating cutter 27 is driven to oscillate about a center support shaft, similarly to the above-mentioned oscillating cutter 6, but is formed into a substantially semicircular shape having an opening angle of 180 degrees about this oscillating center. Is formed. When each oscillating cutter 27 is in the neutral position, the pair of overhangs 27b is at the position indicated by the solid line. For example, when the left oscillating cutter 27 swings clockwise, one pair of overhangs 27b is provided. At the position indicated by the dashed line, and when swinging in the counterclockwise direction, the pair of overhangs 27b is at the position indicated by the two-dot chain line.

When excavating an elliptical shield pit while moving forward by this shield excavator 1C, the cutter disk 26 is rotated by a rotary drive mechanism while a reaction force is applied to the reinforced segment by a plurality of shield jacks, A pair of rocking cutters 27 is provided by a pair of rocking drive mechanisms.
Is reciprocated by a predetermined angle. The central part of the elliptical shield pit is excavated by the cutter disk 26, and the left and right sides of the central part are excavated by the pair of swinging cutters 27. Are excavated at two locations by two pairs of overhangs 27b.

In the case of the shield machine 1C, there is no need to provide means for independently driving the two pairs of overhang portions 27b, so that the configuration of the driving means is simplified. Further, since the shape of the overhang portion 27b can be set quite freely, the degree of freedom in setting the cross section of the shield shaft is increased. However, it is necessary to set the positions of the drum member 12 and the cylindrical connecting member 13 so that the projecting portion 27b does not interfere with the cylindrical connecting member 13.

4) In the shield machine, the distance between the center of the cutter disk 3 and the support shaft of the swing cutter 6 can be changed as appropriate. In addition, a pair of swing cutters 6
Are arranged on both the left and right sides of the cutter disk 3, respectively.
A pair of swing cutters 6 may be arranged on both upper and lower sides of the cutter disk 3.

5) The shape of the pair of swing cutters 6 is
The shape is not limited to the fan shape, and can be set to various shapes. Further, as a form of the swing drive, in addition to the swing by the reciprocating rotation about the support shaft as in the above-described embodiment, the swing drive may be performed so as to make a circular motion in a crank motion. In addition, without departing from the spirit of the present invention, various modifications may be added to the embodiments described above.

[0050]

According to the first aspect of the present invention, a cutter disk, a pair of planetary cutters, a rotary drive unit, a pair of swing cutters, and a pair of swing drive units are provided, so that a rotating cutter is provided. Efficiently excavating the central part of an elliptical shield pit with a disk and a pair of planetary cutters that rotate and rotate, and a pair of swinging cutters that are driven to swing, left and right sides or upper and lower sides of the center part. Can be drilled. Since a pair of planetary cutters is provided, the configuration for excavating the central portion of the elliptical shield pit into a non-circular shape can be simplified, and the manufacturing cost can be reduced.

Further, since the shape of the pair of swing cutters can be set almost freely and the shape of the pair of planetary cutters can be set variously, the degree of freedom in setting the shape of the elliptical shield shaft is remarkable. Can be increased. In addition, since there is no unexcavated area protruding from the inside of the tunnel on the outer periphery of the tunnel, it is possible to increase the utilization rate of the space inside the tunnel, and there is no need to cover the tunnel with a special steel segment. Work costs can be reduced. In addition, since both the rotary drive unit and the pair of swing drive units can be configured to have a relatively simple configuration, their manufacturing costs can be reduced.

According to the second aspect of the present invention, since the pair of swing cutters is disposed so as to be shifted rearward with respect to the cutter disc, interference between the cutter disc and the planetary cutter and the swing cutter is prevented. In addition, the digging area of the cutter disk and the planetary cutter and the digging area of the pair of swing cutters can be partially overlapped to enhance the digging performance. The other effects are the same as those of the first aspect.

According to the third aspect of the present invention, the swinging cutter is formed in a sector shape having an opening angle larger than 180 degrees when viewed from the front, so that the swinging cutter does not largely overlap with the excavation area formed by the cutter disk and the planetary cutter. The shape of the oscillating cutter can be set, and the width of the excavated cross section can be increased. The other effects are the same as those of the first or second aspect.

According to the fourth aspect of the present invention, since the swing driving means is configured to swing the swing cutter back and forth by a predetermined angle around its support shaft, the structure of the swing driving means can be simplified. The manufacturing cost of the shield machine can be reduced. The other effects are the same as those of the third aspect.

According to the fifth aspect of the present invention, since the rotation speed ratio between the planetary cutter and the cutter disk is 4: 1, by rotating the cutter disk and the pair of planetary cutters by the rotation driving means, It can be excavated in a substantially square cross section and cannot be excavated with a cutter disk. 4
One corner can be reliably excavated with a pair of planetary cutters. Other effects similar to those of any one of the first to fourth aspects are exhibited.

According to the sixth aspect of the present invention, since the cutter disk, the rotary drive means, the pair of swing cutters, the pair of swing drive means, and the like are provided, the central portion of the elliptical shield well is excavated with the cutter disk. Then, the left and right sides or the upper and lower sides of the central portion can be excavated with a pair of swing cutters. In addition, since the shape of the pair of swing cutters can be set almost freely, the degree of freedom in setting the shape of the elliptical shield shaft can be greatly increased. In addition, if the shape of the swing cutter is appropriately set, there is no unexcavated area that protrudes to the inside of the tunnel at the outer periphery of the tunnel. Since there is no need to lining with a segment made of steel, tunnel lining costs can be reduced. In addition, since both the rotary drive unit and the pair of swing drive units can be configured to have a relatively simple configuration, their manufacturing costs can be reduced.

According to the seventh aspect of the present invention, the oscillating driving means is constituted so as to reciprocate the oscillating cutter reciprocally around the support shaft by a predetermined angle. Since a pair of overhangs for excavating the unexcavated areas are provided integrally, four areas unexcavated with the cutter disk are efficiently excavated with two pairs of overhangs of a pair of swinging cutters. can do. The overhanging portion can have a simple structure, and can be oscillated by the oscillating driving means, so that no special driving means is required. This is very advantageous in terms of manufacturing cost. In addition, since the shape of the overhang portion can be freely set, the degree of freedom in setting the elliptical shape can be increased. The other effects are the same as those of the sixth aspect.

According to the eighth aspect of the present invention, the oscillating drive means is constituted so as to reciprocate the oscillating cutter around the support shaft by a predetermined angle, and the digging is performed by the cutter disk and the pair of oscillating cutters. Since four drum cutters for excavating the remaining area are provided, the area left to be excavated by the cutter disk and the pair of swing cutters can be reliably excavated by the four drum cutters. The means for rotationally driving the four drum cutters may have a simple configuration, which is advantageous in terms of drive control, and can be manufactured at low cost. The other effects are the same as those of the sixth aspect.

[Brief description of the drawings]

FIG. 1 is a cross-sectional plan view of a main part of a shield machine according to an embodiment of the present invention.

FIG. 2 is a front view of the shield machine.

FIG. 3 is a sectional view taken along line III-III in FIG. 1;

FIG. 4 is an explanatory diagram of a movement locus of a planetary cutter of a shield machine.

FIG. 5 is a schematic front view of a shield machine according to a first modification.

FIG. 6 is an explanatory diagram of a movement locus of a planetary cutter of the shield machine shown in FIG. 5;

7 is an explanatory diagram of a contour shape of a planetary cutter of the shield machine shown in FIG. 5;

FIG. 8 is a schematic front view of a shield machine according to a second modification.

FIG. 9 is a schematic front view of a shield machine according to a third modification.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1, 1A, 1B, 1C Shield machine 3 Cutter disk 4 Planetary cutter 5 Rotation drive mechanism 6 Swing cutter 7 Swing drive mechanism 21 Support shaft 25 Swing cutter 26 Cutter disk 27 Swing cutter 27b Overhanging part 28 Drum cutter

Continuation of the front page (72) Inventor Seiichi Matsushita 1-7-1 Kyobashi, Chuo-ku, Tokyo Toda Construction Co., Ltd. F term (reference) 2D054 AB01 AC01 BA09 BA10

Claims (8)

[Claims] 1. A shield machine which excavates while advancing an elliptical shield mine having a substantially elliptical cross section, comprising: a cutter disk provided at a front end of the shield machine; and a pair of cutter disks provided at a front surface of the cutter disk. A planetary cutter, a rotation driving means for integrally rotating and driving the cutter disc and the pair of planetary cutters and rotating the pair of planetary cutters, and a plurality of planetary cutters arranged on both left and right sides or upper and lower sides of the cutter disc. A shield excavator comprising: a pair of swing cutters; and a pair of swing drive means for respectively swinging the swing cutters. 2. The shield machine according to claim 1, wherein the pair of swing cutters are disposed so as to be shifted rearward with respect to a cutter disk. 3. The swing cutter has an open angle of 1 when viewed from the front.
The shield machine according to claim 1 or 2, wherein the shield machine is configured in a sector shape larger than 80 degrees. 4. The shield machine according to claim 3, wherein the swing driving means is configured to swing the swing cutter back and forth by a predetermined angle around its support shaft. 5. The rotation speed ratio of the planetary cutter to the cutter disk is 4: 1.
A shield machine according to any one of claims 1 to 4. 6. A shield excavator for excavating an elliptical shield pit having a substantially elliptical cross section, a cutter disk provided at a front end of the shield excavator, a rotary drive unit for rotating and driving the cutter disk, and the cutter disk. A shield excavator comprising: a pair of rocking cutters disposed on both left and right sides or upper and lower sides of the rocking cutter; and a pair of rocking drive means for respectively rocking and driving these rocking cutters. 7. The swing drive means is configured to swing the swing cutter back and forth by a predetermined angle around its support shaft,
7. The shield machine according to claim 6, wherein a pair of projecting portions for excavating regions left uncut by the cutter disk are integrally provided at both ends of each swing cutter. 8. The swing drive means is configured to swing the swing cutter back and forth by a predetermined angle around its support shaft,
The shield machine according to claim 6, further comprising four drum cutters each of which excavates an area left unexcavated by the cutter disc and the pair of swing cutters.