JP2009203732A - Shield machine and excavation unit recovery method for shield machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a shield machine constituted by assembling an excavation unit 2 having a cutter head 22 for excavating the ground in front of a shield cylinder on the shield cylinder 1, forming the excavation unit to have a bulkhead 21 to be internally fitted into a ring body 16 fixed at the inner periphery of a front part of the shield cylinder, supporting the cutter head for contracting its diameter to size of inside diameter of the ring body or less on the bulkhead, and removing a stopper 23 for fixation of the bulkhead 21 to recover the excavation unit by letting the bulkhead leave toward the back of the ring body and improve workability in the work for recovering the excavation unit. <P>SOLUTION: In this shield machine, a driving source 25 for letting the cutter head 22 advance and retreat in the forward and backward directions is mounted on the bulkhead 21. A recessed part 16b which is recessed outward in the radial direction and in which an outer end part in the radial direction of the cutter head 22 is fitted by letting the cutter head 22 retreat for the bulkhead 21 while diameter of the cutter head 22 is contracted and then extending the diameter of the cutter head 22 is formed at the inner periphery of a front end part of the ring body 16. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a shield excavator in which a drilling unit having a cutter head for excavating the ground in front of the shield cylinder is attached to the shield cylinder, and an excavation unit recovery for recovering the excavation unit after excavating a tunnel with the shield excavator Regarding the method.

  In underground tunnel construction, a shield excavator is generally excavated from the starting shaft side to the reaching shaft side. Then, after excavating the tunnel, the excavation unit is collected on the ground through the reaching shaft and reused. However, when the reaching shaft is an existing narrow shaft, or when the reaching shaft is not provided, such as when two shield excavators are docked in the ground, the excavation unit should be recovered and reused. Becomes difficult.

  Conventionally, a shield excavator in which a drilling unit can be recovered and reused even in such a case is known from Patent Document 1. In this structure, a ring body having an inner diameter smaller than the inner diameter of the other part of the shield tube is fixed to the inner periphery of the front portion of the shield tube, and the excavation unit has a partition wall fitted into the ring body. A cutter head that can be reduced in diameter to be smaller than the inner diameter of the body is pivotally supported. In addition, the partition wall can be retracted relative to the ring body by releasing the fixing to the ring body.

  According to this shield excavator, after excavation of the tunnel is completed, the fixing of the bulkhead to the ring body is released, and the bulkhead is pulled rearward with the cutter head reduced in diameter, so that the entire excavation unit is moved to the rear of the ring body. Can be pulled out. Then, the excavation unit can be recovered to the ground through the tunnel and the starting shaft.

Here, in the above-mentioned conventional example, the tip of the tow rope is connected to the partition wall, and the partition wall is pulled out rearward of the ring body by pulling the rope backward. However, since the partition wall is slightly tilted due to the uneven load from the heavy cutter blade, the partition wall is twisted with respect to the ring body, and the work of pulling the partition wall from the ring body becomes very troublesome.
Japanese Patent No. 3836467

  In view of the above points, the present invention provides a shield excavator that improves the above-described conventional example so that the partition wall can be easily detached from the ring body, and a method for recovering an excavation unit using the shield excavator. Is the issue.

  In order to solve the above problems, a first invention of the present application is a shield excavator in which a drilling unit having a cutter head for excavating a front ground of a shield cylinder is assembled to the shield cylinder, and the front inner circumference of the shield cylinder In addition, a ring body having an inner diameter smaller than the inner diameter of the other part of the shield cylinder is fixed, and the excavation unit has a partition wall that fits inside the ring body. The head is pivotally supported, and the partition wall can be retracted relative to the ring body by releasing the fixing to the ring body. The cutter head is supported by the partition wall so as to be movable in the front-rear direction. An advancing / retreating drive source that advances and retreats in the direction is mounted, and the radially outer end of the cutter head is expanded on the inner periphery of the front end of the ring body after the cutter head is retracted and then expanded with respect to the partition wall. To focus, wherein the recess is recessed radially outward is formed.

  The second invention of the present application is a method of recovering the excavation unit of the shield excavator after excavating the tunnel with the shield excavator of the first invention, wherein the cutter head is reduced in diameter after excavation of the tunnel is completed. A step of retracting the cutter head with respect to the partition wall by the operation of the advance / retreat drive source in a state where the cutter head is retracted, and then fitting a radially outer end of the cutter head into the recess; and the ring body of the partition wall The cutter head is moved forward with respect to the partition wall by operating the advancing / retreating drive source in a state in which the fixing of the cutter head is released, and the partition head is retracted with respect to the ring body with the recess as a reaction force, and the diameter of the cutter head is reduced. And a step of detaching the radially outer end from the recess and pulling out the entire excavation unit to the rear of the ring body.

  As described above, when the radially outer end portion of the cutter head is fitted into the recess formed in the inner periphery of the front end portion of the ring body, the cutter head cannot move forward relative to the ring body. Therefore, when the cutter head is moved forward with respect to the partition wall, the concave portion receives a reaction force and the partition wall moves backward with respect to the ring body. Further, by fitting the outer end of the cutter head in the radial direction into the concave portion, the weight of the cutter head is received by the ring body, and the offset load by the cutter head does not act on the partition wall. Therefore, the partition wall can be easily pushed out from the ring body without causing a twist to the ring body by the operation of the advance / retreat driving source. Thereafter, if the cutter head is reduced in diameter and its radially outer end portion is detached from the recess, the entire excavation unit can be pulled out behind the ring body, and the workability of the excavation unit recovery work is improved.

  FIG. 1 shows a shield excavator according to an embodiment of the present invention for excavating a tunnel in the ground. The shield excavator includes a shield cylinder 1 and an excavation unit 2 assembled to the shield cylinder 1. The shield cylinder 1 is composed of a front cylinder 11 and a rear cylinder 12. At the front end of the rear cylinder 12, a spherical joint portion 13 that is fitted into the rear end portion of the front cylinder 11 is provided, and the front cylinder 11 can be bent in any direction with respect to the rear cylinder 12. Then, a plurality of middle folding jacks 14 for connecting the front cylinder 11 and the rear cylinder 12 are provided at intervals in the circumferential direction, and the direction of the front cylinder 11, that is, the direction in which the shield excavator is advanced by the middle folding jack 14 is provided. It can be adjusted.

  The rear cylinder 12 is provided with an erector 3 for assembling the segment S in a ring shape on the inner wall surface of the excavated tunnel, and a propulsion jack 15 for advancing the shield cylinder 1 using the installed segment S as a reaction force. A plurality are attached at intervals in the circumferential direction. A tail seal 12 a that seals the gap between the segment S is attached to the rear end of the rear cylinder 12. Further, a ring body 16 having an inner diameter smaller than the inner diameter of the other part of the shield tube 1 is integrally fixed to the inner periphery of the front portion of the front tube 11.

  The excavation unit 2 includes a partition wall 21 fitted in the ring body 16 and a cutter head 22 supported by the partition wall 21 for excavating the front ground of the shield tube 1. On the outer periphery of the partition wall 21, as clearly shown in FIG. 2, there is provided a cylindrical flange portion 21 a that is liquid-tightly fitted into the ring body 16 via a seal 16 a. Moreover, the stopper member 23 which contact | abuts to the rear end of the flange part 21a is attached to the front cylinder 11 so that attachment or detachment is possible. Accordingly, the partition wall 21 is fixed to the ring body 16 by the stopper member 23 so as not to be retractable.

  The cutter head 22 is supported by a partition wall 21 at a shaft portion 22a extending rearward so as to be rotatable and movable in the front-rear direction. A rotary drive source 24 for the cutter head 22 composed of an electric motor is mounted on the rear surface of the partition wall 21, and a drive gear 24a on the output shaft of the rotary drive source 24 is engaged with a spline portion 22b formed on the shaft portion 22a. Is engaged with the driven gear 24b. In addition, the partition wall 21 is provided with a pair of front and rear case portions 21b and 21c that pivotally support the shaft portion 22a in the front-rear direction before and after the spline portion 22b. An advancing / retreating drive source 25 for the cutter head 22 made of a hydraulic jack is attached to the rear end of the rear case portion 21c. The advance / retreat drive source 25 normally holds the cutter head 22 at a position ahead of the front end of the shield tube 1. Thus, when the shield cylinder 1 is advanced by the propulsion jack 15, the propulsive force of the propulsion jack 15 is transmitted to the cutter head 22 via the stopper member 23 and the partition wall 21, and the cutter head 22 excavates the front ground of the shield cylinder 1. However, it moves forward integrally with the shield tube 1.

  As shown in FIG. 3, the cutter head 22 includes a plurality of radial spokes 22d to which a cutter bit 22c is attached and an extension jack (not shown) built into each of the cutter spokes 22d from the outer end of each of the cutter spokes 22d. And an overcutter 22e that protrudes outward in the radial direction. The cutter head 22 can be switched between an expanded state of substantially the same diameter as the outer diameter of the shield tube 1 and a reduced diameter state equal to or smaller than the inner diameter of the ring body 16 by the appearance of the overcutter 22e. In addition, the cutter head 22 includes a face plate 22f positioned between the respective cutter spokes 22d. The face plate 22f has an opening 22g for taking excavated soil into the earth and sand chamber 26 between the cutter head 22 and the partition wall 21. The opening 22g can be opened and closed by a shutter (not shown).

  In the lower part of the partition wall 21, a soil discharge port 21 d communicating with the earth and sand chamber 26 is provided. The screw conveyor 4 as a soil discharging means for discharging the excavated soil in the plastic flow state in the sediment chamber 26 is connected to the soil discharge port 21d. The screw conveyor 4 is disposed in a rearwardly inclined posture. Then, the excavated soil is dropped from the discharge port 4a at the rear end of the screw conveyor 4 onto a belt conveyor (not shown) installed in the excavated tunnel, and the excavated soil is carried out of the mine via the belt conveyor. ing.

  Further, on the inner periphery of the front end portion of the ring body 16, the cutter head 22 is retracted with respect to the partition wall 21 while the diameter of the cutter head 22 is reduced, and then the diameter of the cutter head 22 is increased to increase the diameter, that is, the over cutter 22e. A recess 16b that is recessed radially outwardly is formed in which the outer end of each is fitted. In addition, although the recessed part 16b may be formed discontinuously in the circumferential direction so that the outer end part of each overcutter 22e fits individually, in this case, the circumferential direction position of each overcutter 22e is set to each recessed part. In order to adjust to the position of 16b, the phase control of the cutter head 22 is required. Therefore, in the present embodiment, an annular recess 16b that is continuous in the circumferential direction is formed.

  After the tunnel excavation is completed, the excavation unit 2 is collected for reuse. In this collection operation, first, the diameter of the cutter head 22 is reduced, the cutter head 22 is moved backward with respect to the partition wall 21 by the operation of the advancing / retreating drive source 25, and then the diameter of the cutter head 22 is increased, whereby FIG. As shown in FIG. 5, the outer end portion of the overcutter 22e is fitted into the concave portion 16b on the inner periphery of the front end portion of the ring body 16. Note that when the diameter of the cutter head 22 is increased after retreating, the cutter head 22 is slowly rotated. Thereby, even if the recessed part 16b is buried with soil, the overcutter 22e reliably fits into the recessed part 16b while scraping the soil by the rotation.

  Next, the erector 3, the screw conveyor 4, the folding jack 14, the propulsion jack 15 and the stopper member 23 are removed, and then the cutter head 22 is advanced relative to the partition wall 21 by the operation of the advance / retreat drive source 25. At this time, due to the fitting of the overcutter 22e to the recess 16b, the cutter head 22 cannot advance with respect to the ring body 16, while the stopper member 23 is removed. That is, the ring body 16 can be retracted. Therefore, as shown in FIG. 4B, the partition wall 21 moves backward with respect to the ring body 16 with the recess 16b (precisely, the front wall of the recess 16b) as a reaction force receiver. Further, the weight of the cutter head 22 is received by the ring body 16 due to the fitting of the overcutter 22e to the recess 16b, and the offset load due to the cutter head 22 does not act on the partition wall 21. Accordingly, the partition wall 21 can be easily pushed out of the ring body 16 without causing a twist with respect to the ring body 16 by the operation of the advance / retreat driving source 25.

  Next, as shown in FIG. 4 (c), the rail 5 is positioned between the ring body 16 and the segment S at the lower and upper portions of the inner surface of the shield cylinder 1 so as to be flush with the inner surface of the segment S. At the same time, the roller 6 on the rail 5 is attached to the rear end of the flange 21a of the partition wall 21. The rail 5 and the roller 6 may be attached before the partition wall 21 is moved backward with respect to the ring body 16. Thereafter, the cutter head 22 is reduced in diameter, the overcutter 22e is detached from the recess 16b, and the entire excavation unit 2 is pulled out to the rear of the ring body 16 as shown in FIG. At this time, when the partition wall 21 is completely pulled out from the ring body 16, a roller 6 ′ on the rail 5 is attached to the front surface of the partition wall 21, and the cutter head 22 is moved backward with respect to the partition wall 21. Thereby, the excavation unit 2 can move stably in the tunnel. Then, the excavation unit 2 can be collected on the ground through the tunnel and the start shaft and reused.

  If the cutter head 22 is movable in the front-rear direction with respect to the partition wall 21 as in this embodiment, the cutter bit 22c can be exchanged during tunnel excavation. That is, by retracting the cutter head 22 with respect to the partition wall 21, a work space can be secured between the face and the cutter head 22, and the cutter bit 22c can be replaced.

The longitudinal cross-sectional view of the shield excavator of embodiment of this invention. The expanded longitudinal section of the important section of the shield excavator of an embodiment. The front view of the cutter head of the shield excavator of an embodiment. Explanatory drawing which shows the collection | recovery operation procedure of the excavation unit of the shield excavator of embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Shield pipe | tube, 16 ... Ring body, 16b ... Recessed part, 2 ... Excavation unit, 21 ... Bulkhead, 22 ... Cutter head, 25 ... Forward / backward drive source

Claims (2)

A shield excavator in which a drilling unit having a cutter head for excavating the front ground of the shield cylinder is assembled to the shield cylinder,
A ring body having an inner diameter smaller than the inner diameter of the other part of the shield tube is fixed to the inner periphery of the front portion of the shield tube, and the excavation unit has a partition wall that fits inside the ring body. A cutter head whose diameter can be freely reduced is pivotally supported, and the partition wall can be retracted relative to the ring body by releasing the fixing to the ring body
The cutter head is supported by the partition wall so as to be movable in the front-rear direction, and the partition wall is equipped with an advancing / retreating drive source for moving the cutter head back and forth in the front-rear direction.
In the inner periphery of the front end of the ring body, the cutter head is retracted with respect to the partition wall in a reduced diameter, and then the diameter is increased to fit the outer end of the cutter head in the radial direction. A shield excavator characterized in that a recess is formed. A method for recovering the excavation unit of a shield excavator after excavating a tunnel with the shield excavator according to claim 1,
After the excavation of the tunnel is completed, the cutter head is retracted with respect to the partition wall by the operation of the advance / retreat drive source in a state where the cutter head is reduced in diameter, and then the diameter is expanded, and the radially outer end portion of the cutter head is the recess. Mating with
A step of moving the cutter head forward with respect to the partition wall by operating the advancing / retreating drive source in a state where the partition wall is fixed to the ring body, and retracting the partition wall with respect to the ring body by receiving the recess as a reaction force;
A method for recovering an excavation unit of a shield excavator, comprising: a step of reducing the diameter of the cutter head to disengage the radially outer end of the cutter head from the recess and pulling the entire excavation unit to the rear of the ring body.

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