JPH09303080A - Enlarging shield excavating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve work efficiency and reduce cost with simple constitution by installing a motor for a cutter, and rotating a turning base fitted with a header so as to move a shield body along the longitudinal direction of an existing tunnel. SOLUTION: After breaking lining 3 by an inner circumferential surface excavating cutter 45, the natural ground is enlargedly excavated, and the inner circumferential surface excavating cutter 45 is pushed forward in a diameter outer direction by jacks 46, 46. At this time, high pressure water is jetted to the excavating face from nozzle holes so as to cool each roller cutter and its peripheral part heated by frictional treat at the time of excavation and to wash clay stuck to the excavating face. Each roller cutter and its peripheral part are thereby prevented from being deformed or damaged by heat so as to improve the bite of each roller cutter into the natural ground and thereby to heighten excavating efficiency. The shape of an enlarged tunnel 4 can be made into optional shape such as horseshoe shape in addition to circular shape by adjusting the drawing distance of a header 37.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an enlarged shield excavator, and more particularly, to crush the lining of an existing tunnel having a circular shape or a horseshoe shape to newly form a large diameter circular or horseshoe shape tunnel. The present invention relates to a suitable enlarged shield excavator.

[0002]

2. Description of the Related Art When expanding an existing tunnel to excavate a large-diameter tunnel, the lining composed of segments and fume pipes is crushed, then a new large-diameter tunnel is excavated, and then the large-diameter tunnel is excavated. It is usual to apply a large diameter lining to the inner wall of the enlarged tunnel.

In recent years, various devices have been developed which are capable of simultaneously performing the two operations of crushing the lining and excavating an enlarged tunnel. For example, JP-A-6-2881
The one disclosed in Japanese Patent Publication No. 75 advances in the ground while rotating a tubular main body and reinforces the formed tunnel wall surface with segments.

In this device, the lining of an existing circular tunnel to be crushed is positioned at the center of the inside of the shield body, and the lining is crushed by being sandwiched by the roller cutter from the inside and the outside. . Further, the crushed waste is transferred backward by a conveyor. By adopting such a configuration, there is an advantage that the crushing of the lining of the existing tunnel and the construction of the new tunnel having the enlarged inner diameter can be simultaneously advanced.

[0005]

However, in the above-mentioned conventional enlarged shield excavating device, since two sets of crushing cutters are arranged and fixed inside and outside the existing lining, the inside diameter and the outside diameter are specific. It is difficult to adapt it to anything other than a lining having a shape and dimensions, and it is difficult to apply it when, for example, the existing tunnel has a non-circular cross section such as a horseshoe. In addition, the tunnel shape after expansion was limited to a circular shape, and it was not possible to expand it into a horseshoe-shaped tunnel. Further, since the inside and the outside of the lining are sandwiched by the roller cutter and crushed, there is a problem that the structure is complicated and the cost becomes high.

The present invention has been made in order to solve the above conventional problems, and is applicable regardless of the shape of an existing tunnel to be crushed, and can be expanded to a circular or horseshoe-shaped tunnel. (EN) An expanded shield excavating device having a simple structure and inexpensive.

[0007]

The present invention is an enlarged shield excavator, which is configured as follows in order to solve the above-mentioned technical problems. That is, the enlarged shield excavating device of the present invention is an enlarged shield excavating device for crushing a lining of an existing tunnel using an inner peripheral surface excavating cutter and excavating a tunnel having a larger diameter than the existing tunnel. A cutter motor for driving a cutting cutter is attached, a header that can be extended in the radial direction of the existing tunnel, a swivel to which the header is attached, a drive unit that rotates the swivel, the header, and It is characterized by further comprising a shield main body for holding the swivel base and the driving means, and a moving means for moving the shield main body along the longitudinal direction of the existing tunnel. Hereinafter, each component will be described. (Inner peripheral surface excavating cutter) As the inner peripheral surface excavating cutter of the expanded shield excavating device to which the present invention is applied, a cutter capable of crushing the lining and excavating the natural ground can be used. (Cutter Motor) As the cutter motor, a normal motor can be used. (Header) As the header, a cylindrical one to which a cutter motor can be attached is used, and the header can be doubled so as to be extendable in the radial direction by a jack, for example. (Swivel base) As the swivel base, a disc-shaped rotatable base with a header attached can be used. (Driving Means) As the driving means, a hydraulic motor and gears for transmitting the rotational torque thereof to the swivel can be used. (Shield main body) As the shield main body, a bottomless cylindrical body can be used, and a header, a swivel base, and a driving means can be attached to the inside thereof. (Moving means) As the moving means, for example, a jack or the like can be used.

The expanded shield excavating device of the present invention is composed of the above-mentioned essential components, but is also established when the following components are added in addition to these components. The constituent element is that the inner peripheral surface excavating cutter excavates the inner peripheral surface of the existing tunnel in the radial direction as the header extends. Further, the inner peripheral surface excavating cutter excavates the inner peripheral surface of the existing tunnel in a radial direction as the header extends, and excavates the existing tunnel in a peripheral direction as the header rotates. Is.

In the expanded shield excavating device of the present invention, the inner peripheral excavating cutter moves in the radial direction of the existing tunnel by extending the header, and the lining is first crushed in the radial direction from the inner surface side. Then, the ground on the outer side of the lining is excavated to a predetermined diameter by approximately the diameter of the inner peripheral surface excavating cutter. By continuously performing the excavation operation in the circumferential direction of the existing tunnel by rotating the swivel base, excavation for approximately one round of the expansion tunnel is completed. Next, the shield body is moved forward by the moving means by about the diameter of the inner surface excavating cutter, and the lining is crushed and the expanding tunnel is excavated for about one round, as described above. In this way, excavation of the expanded tunnel is completed by crushing the lining and excavating the ground while advancing the shield body along the existing tunnel.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The enlarged shield excavating device according to the present invention will be described in detail below with reference to the illustrated embodiments.

FIG. 1 shows a state of use of the enlarged shield excavation device 1 according to the present invention. This expanded shield excavator 1
Is a shield body 10 that can be fixed to the inner peripheral surface of the lining 3 of the existing tunnel 2, an excavation section 11 attached to the rear end of the shield body 10 for crushing the lining 3 and excavating the enlarged tunnel 4, and a shield. A moving part 12 for advancing the main body 10 along the longitudinal direction of the existing tunnel 2.
And

The shield body 10 is a bottomless, large-diameter cylindrical portion 1
3 has an outer diameter smaller than that of the lining 3. As shown in FIG. 2, a plurality of bottomed and long frame portions 14 are radially attached to the front and rear of the cylindrical portion 13. Then, as shown in FIG. 1, a plurality of hydraulically driven gripper jacks 15 are mounted in the frame portion 14.

At the time of excavation, the rod 17 of the hydraulic piston 16 of the gripper jack 15 is projected, and the lining 3 of the existing tunnel 2 is pressed by the grip 18 at the tip thereof to fix the shield body 10. The grip 18 is inclined at an angle corresponding to the lining 3 of the existing tunnel 2 or the rail base 19 as shown in FIG.

The cylindrical portion 13 of the shield body 10 has a structure shown in FIG.
As shown in, a hydraulically driven moving jack 20 is attached to the lower side of the front end portion. This moving jack 2
The tip of the telescopic rod 21 of 0 is attached to the bracket 22 of the rail base 19. Further, as shown in FIG. 2, wheels 23 are attached to the bottom of the cylindrical portion 13 at appropriate intervals.

The moving part 12 includes a rail base 19 laid on the bottom of the existing tunnel 2 and a pair of rails 24, 24 fixed in parallel on the rail base 19. On the rails 24, 24, the wheels 23 of the shield body 10,
23 is on board. Then, the movable jack 20 (FIG. 1) of the shield body 10 is operated to move the telescopic rod 21.
When the shield is retracted, the shield body 10 can be moved forward. On the contrary, if you push out the telescopic rod 21,
The shield body 10 can be retracted.

A swivel base 25 is built in the rear end of the cylindrical portion 13 of the shield body 10, and the excavation unit 11 is attached to the rear surface of the swivel base 25. Further, on the front surface of the swivel base 25, a double shaft cylinder 26 having a smaller diameter than the swivel base 25 is attached. An internal gear 27 is attached to the shaft cylinder 26.

A hydraulic motor 28 rotationally drives the swivel base 25, and an external gear 29 meshing with an internal gear 27 is attached to an output shaft of the hydraulic pressure 28. Hydraulic motor 2
The rotation torque of No. 8 is reduced by the external gear 29 and the internal gear 27 and transmitted to the swivel base 25. The swivel base 25 rotates about a rotary shaft 30 rotatably attached to the cylindrical portion 13 of the shield body 10. The hydraulic motor 28 is attached to a collar member 31 extending inside the shield body 10. For example, four hydraulic motors 28 can be mounted on the circumference of the collar member 31.

A swivel base bearing 32 for rotatably supporting the internal gear 27 in the thrust direction is attached to the collar member 31. Further, a housing 34 incorporating a radial bearing 33 that rotatably supports the barrel 26 is attached to the collar member 31.

Next, the excavation section 11 will be described. The excavation section 11 includes an outer box 35 having a rectangular cross section attached to the swivel base 25, and an inner box 36 arranged in the outer box 35. A header 37 is arranged in the inner box 36. The header 37 has a cylindrical base portion 38, and a cylindrical rod 39 is inserted thereinto so as to be expandable and contractible. Base 3
As shown in FIG. 2, a horizontal shaft 40 is provided at the lower end of 8 and is fixed to the inner box 36.

A rotary shaft 41 is rotatably mounted inside the rod 39, and one end of the rotary shaft 41 is connected to a motor 42 in the rod 39. The other end of the rotary shaft 41 projects from the header 37, and an inner peripheral surface excavating cutter 45 is attached to the end surface of the rotary shaft 41.

Inside the inner box 36, jacks 46, 46 located on both sides of the header 37 are arranged, and their cylinder portions 46A, 46A are fixed to the inner bottom surface of the outer box 35.
Also, the telescopic rods 46B, 46B of the jacks 46, 46
Is attached to the side surface of the rod 39. Then, by operating the jacks 46, 46,
The inner peripheral surface excavating cutter 45 can be moved within a predetermined range in the radial direction of the existing tunnel 2.

As shown in FIG. 3, the inner peripheral surface excavating cutter 45 includes a base 120 and a plurality of roller cutters rotatably attached to the base 120. In this example, a large roller cutter 121, a middle roller cutter 122, Small roller cutter 1
23 and scrapers 125A, 12 for discharging the scrap 168 (FIG. 5) excavated by the roller cutters 121 to 123.
5B and.

The base 120 has a plate 131 which can be detachably attached to the rotary shaft 41 with, for example, a bolt 117. As shown in FIG. 4, the plate 131 includes a first protrusion 132 and a second protrusion 1 around the disk.
33, the third projecting portion 134, and the fourth projecting portion 135 are provided at equal intervals. First protrusion 132 and third protrusion 1
Plate-shaped ribs 136 and 138 extending up to near the center of the plate 131 are erected on both side ends of the plate 34.

At the boundary between the ribs 136 and 138, a rib 150 extending perpendicularly to the ribs 136 and 138 up to near the roots of the second protruding portion 133 and the fourth protruding portion 135 is provided. In addition, the second protruding portion 133 and the fourth protruding portion 1
The first protruding portion 132 and the third protruding portion 1 are also provided on both side ends of 35.
34 ribs 137, 13 extending to ribs 136, 138
9 are erected.

Ribs 136 on both sides of the first protrusion 132,
As shown in FIG. 3, a plate-shaped first bearing portion 140 and a second bearing portion 141 are fixed between the 136 at predetermined intervals. These first bearing portion 140 and second bearing portion 1
41 is inclined with respect to the plate surface of the plate 131 at an appropriate angle α.

The first bearing portion 140 and the second bearing portion 14
1 is provided with shaft holes 142 and 143 which are perpendicular to the plate surface thereof, and the center shaft 145 of the large roller cutter 121 is inserted into the shaft holes 142 and 143 so as not to come out carelessly. As a result, the large roller cutter 121 is rotatably supported.

The large roller cutter 121 is made of a material having a hardness high enough to crush the lining 3, and has a sharp-angled abacus-shaped blade 146, 147, 148.
Are stacked in multiple stages, in this example, three stages. Each blade 14
The diameters of 6, 147 and 148 are smaller as they are closer to the center of the base 120. The large roller cutter 121 is located on the center side of the base 120, that is, the blade 1
It is inclined so that the 48 side projects.

The rib 150 at the central portion of the plate 131 is provided with a third bearing portion 155 on the upper side (left side in the drawing) thereof. Further, as shown in FIG. 4, fourth bearing portions 156, which are parallel to the third bearing portion 155 and are arranged on the opposite side of the large roller cutter 121 at a predetermined interval, are provided with ribs on both side ends of the third protruding portion 134. It is fixed between 138 and 138. Third bearing portion 155 and fourth bearing portion 156
Are perpendicular to the plate surface of the plate 131.

In the third bearing portion 155 and the fourth bearing portion 156, as shown in FIG. 3, the shaft hole 15 perpendicular to the plate surface is formed.
7, 158 are provided, and the rotary shaft 159 of the middle roller cutter 122 is inserted into these shaft holes 157, 158 so as not to accidentally come out. As a result, the middle roller cutter 122 is rotatably supported in parallel with the plate surface of the plate 131. The middle roller cutter 122 is made of a material having high hardness, and blades 151 having an abacus ball shape are stacked in three stages.

As shown in FIG. 4, the upper ends of the ribs 137 and 137 on both side ends of the second projecting portion 133 and the fourth projecting portion 135.
At the upper ends of the ribs 139 and 139 of the
0 is attached in a tilted manner, and a small roller cutter 123 is arranged inside thereof. Further, as shown in FIG. 3, the rotary shaft 163 of the small roller cutter 123 is inserted into the receiving plates 161 and 162 of the bearing portion 160 so as not to come out carelessly. As a result, the small roller cutter 123 is rotatably supported in an inclined state so that the central side of the plate 131 projects.

The small roller cutter 123 is also made of a material having a high hardness, and has blades 164, 16 having an amber ball shape and a sharp tip.
5, 166 are stacked in three stages. Also, each blade 16
The diameters of 4, 165 and 166 are smaller toward the center of the plate 131.

As shown in FIG. 4, the large roller cutter 12
1, medium roller cutter 122, small roller cutter 123, 1
Scrapers 125A and 125B are arranged on the side of 23. The scraper 125A is provided so as to extend from the upper ends of the ribs 136 and 138 as shown in FIG.
The tip 167 side is inclined so as to project in the rotation direction of the plate 131.

Therefore, when the plate 131 rotates, the scraper 168 excavated by the roller cutters 121, 122, 123 is pressed in the rotational direction of the plate 131 by the scraper 125A, and the excavator 1 is moved along the inclination thereof.
It is pushed out from 81. That is, the drill 168
Will be extruded while being accumulated by the scraper 125A. Scraper 125B is also scraper 125A
But scraper 125B has ribs 137, 1
It extends obliquely from the side of 39 instead of the upper end.

As shown in FIG. 3, a water passage 169 is provided at the center of the rotary shaft 41, and the joint 1 is provided in this water passage 169.
The tube 170 is connected via 80. on the other hand,
As shown in FIG. 4, plates 172 and 172 are provided inside the small roller cutters 123 and 123. Nozzle holes 173 and 173 are provided in the plates 172 and 172, respectively.
Each is provided.

The above-mentioned tube 170 is connected to these nozzle holes 173. Then, the high-pressure water supplied from the outside passes through the water passage 169, the joint 180, and the tube 1.
It is ejected from the nozzle hole 173 via 70. In the figure, reference numerals 175 and 176 denote side covers and reference numerals 177 and 1
Reference numeral 78 is a top cover.

Next, the operation of the expanded shield excavator 1 will be described. As shown in FIG. 1, when the existing tunnel 2 is expanded and excavated by using the expanded shield excavation device 1, first, the hydraulically driven gripper jack 15 is actuated and the gripper 18 at the tip thereof is inserted into the lining 3 of the existing tunnel 2. The expanded shield excavation device 1 is fixed by pressing it against the peripheral surface.

Then, the hydraulic motor 28 is driven to rotate the external gear 29. Then, the internal gear 27 meshing with the external gear 29 is decelerated and rotated, and the axial cylinder 2
The swivel base 25 rotates via 6. Then, when the inner peripheral surface excavating cutter 45 is arranged at the position where the excavation is to be performed, the hydraulic motor 28 is stopped to stop the rotation of the swivel base 25.

Next, the jacks 46, 46 are driven to extend the hollow rod 39 of the header 37, and the inner peripheral surface excavating cutter 45 is pressed against the inner surface of the lining 3. At this time, the operating oil pressure of the jack 46 is kept high.
In this state, when the motor 42 is driven to rotate the rotary shaft 41 as shown in FIG. 2, the inner peripheral surface excavating cutter 45 rotates.

Then, as shown in FIG. 1, the large roller cutter 121 and the intermediate roller cutter 1 of the inner peripheral surface excavating cutter 45.
22, the lining 3 is first crushed by the small roller cutter 123 (FIG. 3), and then the ground 124 is enlarged and excavated. As the excavation of the ground 124 proceeds, the inner peripheral surface excavating cutter 45 is pushed outward by the jacks 46, 46 in the radial direction.

During excavation of the ground 124, the nozzle hole 173
High-pressure water is jetted from (FIG. 3) toward the excavated surface of the rock mass 124, and the roller cutters 121, 122, 123 and their peripheral portions that are heated by friction heat during excavation are cooled by this high-pressure water. At the same time, clay or the like adhering to the excavated surface of the natural ground 124 is washed. As a result, it is possible to prevent the roller cutters 121, 122, 123 and their peripheral portions from being deformed or damaged by heat, and to improve the excavation efficiency by improving the bite of the roller cutters 121, 122, 123 with respect to the natural ground 124. be able to.

Further, as shown in FIG. 5, the scraper 168 excavated by the roller cutters 121, 122, 123 is pushed out of the excavation hole 181 by the scrapers 125A, 125B rotating immediately thereafter. The scrapers 125A and 125B are used for the roller cutters 121 and 12 respectively.
Since it is arranged on the side of 2, 123, the excavated slot 168 can be immediately pushed out. Therefore,
It is possible to prevent the slit 168 from interfering with the excavation work and improve the work efficiency.

In this way, as shown in FIG. 1, when the inner peripheral surface excavating cutter 45 has advanced from the inner peripheral surface of the lining 3 by the depth L, the inner peripheral surface excavating cutter 45 is returned to the original position and the swivel base. 25 is rotated and the inner peripheral surface excavating cutter 45 is pressed against the next planned excavation position.

After that, the lining 3 is crushed and the ground 124 is expanded and excavated by the same procedure as described above. By repeating this, the expansion tunnel 4 can be excavated by a length corresponding to the diameter of the inner peripheral surface excavating cutter 45.

In this way, after the arch portion of the enlarged tunnel 4 is excavated by a length approximately equal to the diameter of the inner peripheral surface excavating cutter 45, the inner peripheral surface excavating cutter 45 and the grip 18 are returned to their original positions. Then, when the moving jack 20 is driven to pull in the rod 21, the rail 24 on the rail base 19,
The wheels 23, 23 rotate along 24, and the expanded shield excavation device 1 moves forward.

The shield 18 can be fixed in a floating state by pressing the lining 3 with a grip 18 other than that corresponding to the rail base 19, and by moving the rail base 19 in this state, the shield main body 10 can be fixed. Can be moved over the entire length of the existing tunnel 2.

After the enlarged shield excavator 1 has advanced by approximately the diameter of the inner surface excavating cutter 45, the grip 18 is moved to the inner surface of the lining 3 of the existing tunnel 2 or the rail base 19.
Then, the expanded shield excavation device 1 is fixed by pressing. Thereafter, the inner surface excavating cutter 45 is used to crush the lining 3 and expand the natural ground 124 in the same manner as described above. The excavated scrap 168 is discharged by, for example, a backhoe.
The excavation of the expansion tunnel 4 is completed by repeating such operations.

When excavating the ground 124, the jack 46
The shape of the enlarged tunnel 4 can be made into an arbitrary shape and size such as a circular shape or a horseshoe shape by appropriately controlling the operation of (1) and adjusting the extending distance L of the inner peripheral surface excavating cutter 45.

As described above, in the expanded shield excavation device 1 of the present invention, the lining 3 and the natural rock 124 are formed by the inner peripheral excavation cutter 45 that can be extended in the radial direction of the existing tunnel 2.
Since it is crushed or excavated in the radial direction, various existing tunnels 2 having different sizes and shapes such as a horseshoe shape and a circular shape can be enlarged and excavated.

Further, by appropriately adjusting the extension distance L of the inner peripheral surface excavating cutter 45 depending on the excavation position as described above, the shape of the enlarged tunnel 4 is not limited to a circular shape, but can be any shape such as a horseshoe shape. . Furthermore, since only one inner peripheral surface excavating cutter 45 is required, the structure is simple and the cost can be reduced.

FIG. 6 shows an inner peripheral surface excavating cutter 200 according to another embodiment. The inner peripheral surface excavating cutter 200 includes a base 201 and a plurality of roller cutters rotatably attached to the base 201. In this example, the top roller cutters 202 and 202, and the corner roller cutters 203 and 204.
(FIG. 8) and side roller cutters 205, 206, 20
7 and 7.

The base 201 is, for example, bolted to the rotary shaft 4
Plate 250 that can be detachably attached to 1
have. As shown in FIG. 7, the plate 250 has a first protrusion 208, a second protrusion 209, a third protrusion 210, and a fourth protrusion 211 having a predetermined width, which are provided at equal intervals around a disk. There is. Ribs 212 to 219 are provided upright on both sides of each of the protrusions 208 to 211.

A rib 220 is provided between the rib 214 of the second protrusion 209 and the rib 219 of the fourth protrusion 211, and the rib 215 of the second protrusion 209 and the fourth protrusion 211 are provided.
A rib 221 is provided between the rib 218 and the rib 218. Then, one continuous rib 214, 220, 21
Four plate-shaped bearing portions 222 are vertically attached at a predetermined interval between the 9 and the other continuous ribs 215, 221, and 218.

These bearings 222 are attached to the tips of the ribs 214, 220 and 219 as shown in FIG. The rotary shaft 223 of the top roller cutter 202 is inserted into the pair of outer and inner bearings 222, 222 of the four bearings 222 at right angles to the central axis of the rotary shaft 41.

In the top roller cutter 202, abacus bead-shaped blades 224 made of a high hardness material are stacked in two stages. A nozzle 225 is provided near the top roller cutter 202, and this is provided with a tube 226 and a joint 22.
7 is connected to the water passage 169 of the rotating shaft 41.

As shown in FIG. 7, two plate-shaped bearing portions 22 are provided between the ribs 214 and 215 of the second projecting portion 209.
8 are laterally installed at a predetermined interval. These bearing portions 228 are slightly inclined as shown in FIG.
The rotary shaft 229 of the corner roller cutter 203 is rotatably inserted into the bearing 228.

The corner roller cutter 203 also has abacus bead-shaped blades 230 made of a high hardness material stacked in two stages. A horizontal nozzle 231 is arranged near the plate 250 near the corner roller cutter 203, and a tube 226 is connected to the nozzle 231.

As shown in FIG. 7, also between the ribs 218 and 219 of the fourth projecting portion 211, two bearing portions 235 are provided laterally at a predetermined interval in the vertical direction. These bearing portions 235 are slightly inclined as shown in FIG. 6, and the rotary shaft 236 of the side roller cutter 205 is rotatably attached. Side roller cutter 205
Is an abacus ball-shaped blade 237 made of a high hardness material.
It is stacked in columns. A lateral nozzle 238 is arranged near the plate cutter 250 near the side roller cutter 205, and a tube 226 is connected to the nozzle 238.

As shown in FIG. 8, the first of the plates 250 is
Between the ribs 212 and 213 of the projecting portion 208, two bearing portions 240, which are located on the upper side, are arranged at a predetermined interval and inclined at an appropriate angle. The rotation shaft 241 of the corner roller cutter 204 is rotatably attached to the bearing 240.

Similarly, the rib 216 of the third protrusion 210,
Between the two parts 217, the two bearing parts 24 are located on the upper side.
2 are arranged so as to be inclined at an appropriate angle.
A rotary shaft 241 of the corner roller cutter 204 is rotatably attached to the corner 2. Corner roller cutter 204
Is an abacus ball-shaped blade 243 made of high hardness material.
It is stacked in columns.

Further, the ribs 212, 2 of the first protrusion 208 are provided.
13 between the corner roller cutter 204 and the plate 2
Two bearing portions 244 are laterally provided at a predetermined distance from each other and located closer to the outer peripheral side of the plate 250. A rotary shaft 245 of the side roller cutter 206 is rotatably attached to the bearing 244. The side roller cutter 206 has two abacus-shaped blades 246 formed of a high hardness material stacked in two stages. Similarly, two bearing portions 244 are laterally provided between the ribs 216 and 217 of the third protruding portion 210, and the rotary shaft 245 of the side roller cutter 206 is rotatably attached thereto.

As shown in FIG. 7, each of the protrusions 208 to 21
A scraper 246 for discharging the excavated scrap 168 (FIG. 5) is provided at the tips of the ribs 213, 215, 217, and 219 on one side of the No. 1 side. Also, the plate 25
0 and ribs 208 to 211 are provided with reinforcing ribs and covers at appropriate positions (reference numerals are omitted).

In addition to the two top cutters 202, 202, the inner peripheral surface excavating cutter 200 includes three corner roller cutters 203, 204, 204 and three side cutters 205, 206. Since the inner peripheral surface excavating cutter 200 is rotated, the inner peripheral surface excavating cutter 200 is rotated and the inner peripheral surface excavating cutter 200 is rotated to rotate the inner peripheral surface excavating cutter 200. It can be crushed or excavated in the circumferential direction.

Therefore, the above-mentioned inner peripheral surface excavating cutter 4
The excavation efficiency is greatly improved compared to the No. 5. Also, swivel 2
By adjusting the extension length of the jack 46 during the rotation of 5, it is possible to efficiently excavate the enlarged tunnel 4 having any shape such as a horseshoe shape as well as a circular shape.

[0064]

As described above, according to the expanded shield excavator of the present invention, the cutter for excavating the inner peripheral surface can be moved in the radial direction of the existing tunnel by the extension of the header. Regardless of this, the lining can be crushed and the ground can be excavated with the same inner peripheral surface excavating cutter, so that the work efficiency is improved. Further, by adjusting the extension distance of the header, the shape of the expansion tunnel can be made not only circular but also arbitrary such as horseshoe. Furthermore, since it is sufficient to provide only one cutter for excavating the inner peripheral surface, the structure can be simplified and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing a usage state of an enlarged shield excavating device according to the present invention.

FIG. 2 is a sectional view taken along line AA of FIG.

FIG. 3 is a view showing a cutter for excavating the inner peripheral surface of the enlarged shield excavating device according to the present invention.

FIG. 4 is a view on arrow B of FIG.

FIG. 5 is a sectional view taken along line CC of FIG. 4;

FIG. 6 is a cross-sectional view showing another embodiment of the inner peripheral surface excavating cutter.

FIG. 7 is a view on arrow D in FIG.

FIG. 8 is a sectional view taken along line EE of FIG. 7;

[Explanation of symbols]

 1 Enlarged Shield Excavator 2 Existing Tunnel 3 Lining 4 Enlarged Tunnel 10 Shield Body 11 Excavator 20 Moving Jack (Moving Means) 25 Revolving Platform 27 Internal Gear (Drive Means) 28 Hydraulic Motor (Drive Means) 29 External Gear (Drive Means) ) 37 header 42 motor for cutter 45 cutter for inner surface excavation

Claims (3)

[Claims] 1. An expanded shield excavating device for crushing a lining of an existing tunnel using an inner peripheral surface excavating cutter and excavating a tunnel having a diameter larger than the existing tunnel, wherein the inner peripheral surface excavating cutter is driven. With a motor for mounting and extending in the radial direction of the existing tunnel, a swivel to which the header is mounted, a driving means for rotating the swivel, the header, the swivel and the driving means An enlarged shield excavating device, comprising: a shield body that holds the shield body; and a moving unit that moves the shield body along a longitudinal direction of the existing tunnel. 2. The expanded shield excavating device according to claim 1, wherein the inner peripheral surface excavating cutter excavates an inner peripheral surface of the existing tunnel in a radial direction as the header extends. 3. The cutter for excavating the inner peripheral surface excavates the inner peripheral surface of the existing tunnel in a radial direction with the extension of the header, and rotates the existing tunnel in the peripheral direction with the rotation of the header. The expanded shield excavating device according to claim 1, which is excavated.