JPH0624476Y2 - Shield machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a shield machine having a shield frame and a tubular body joined to an existing tunnel, for example, and particularly to resistance when extending the tubular body. The present invention relates to a shield machine that can reduce

[Prior Art] A tunnel under excavation may be joined to an existing tunnel or a shield frame of another shield excavator under excavation.

For example, as shown in FIG. 4, when the shield frame 3 of the shield machine 1 under excavation is joined to the existing tunnel 2, the shield machine 1 is stopped in front of the existing tunnel 2 and the shield frame 3 is removed. After removing the cutter 4 and the like, the earth and sand of the joint portion 5 in front of the shield frame 3 is excavated by hand.

At this time, in order to prevent the landslide of the joint 5 after the cutter 4 is removed, conventionally, a method of injecting a ground hardening agent such as cement milk into the ground around the joint 5 to strengthen the ground has been proposed. It was taken.

[Problems to be solved by the invention] However, in the method of strengthening the ground by the above-mentioned ground hardening agent, the effect of the ground hardening agent is doubtful in the sandy ground or the ground with a lot of groundwater, and In a place with a large amount of traffic such as an intersection of roads, there is a problem that the ground is likely to sink due to the traveling vibration of the vehicle. In order to solve this problem, the applicant of the present invention has previously proposed a shield excavator including a protective cylinder that can be projected or retracted around the outer periphery of the tip of the shield frame. In this proposal, as shown in FIG. 4, a protective cylinder (cylindrical body) 6 is provided on the outer circumference of a shield frame 3 having a rotary cutter 4 at the front end in the excavation direction so as to extend forward from the cutter 4. Then, when the tunnel being excavated is joined to the existing tunnel 2, the cylindrical body 6 is extended from the shield frame 3 stopped before the existing tunnel 2 to the ground ahead. That is, the cylindrical body 6 is extended to a position indicated by a chain double-dashed line in the drawing, and the extended cylindrical body 6 surrounds the ground of the joint portion 5 between the shield frame 3 and the existing tunnel 2 to join the two. This is to prevent the landslide of the part 5.

The present invention was created to further improve the above proposal, and its purpose is to excavate the natural ground along the extending direction of the cylinder to reduce the resistance of the cylinder extending. To provide a shield machine.

[Means for Solving the Problems] A cylindrical body is slidably inserted forward from the rotary cutter on the outer periphery of a shield frame having a rotary cutter at the front end in the excavation direction, and the cylindrical body is arranged in the excavating direction. In a shield machine that is moved to the side of an existing object such as an existing tunnel, in the substantially outer peripheral edge portion of the rotary cutter, the earth and sand between the tube and the existing object such as the existing tunnel are transferred to the tube. In order to perform excavation along the extension track, the excavating bit is provided so as to be extendable and contractible in the radially outward and obliquely forward direction of the rotary cutter.

[Operation] The shield machine advances while excavating the natural ground to form a tunnel. When joining the tunnel under excavation to the existing tunnel, for example, the shield frame is stopped in front of the existing tunnel, and the cutter is rotated while extending the excavating bit toward the existing tunnel. As a result, the ground between the tubular body and the existing buried object such as an existing tunnel is excavated along the extension track of the tubular body, so the resistance when the tubular body extends is reduced, and the extension is easy. Becomes

[Embodiment] An embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a side sectional view of a shield machine according to an embodiment of the present invention, showing a state in which the shield machine 1 is stopped in front of an existing tunnel 2.

In the figure, the shield machine 1 has a shield frame 3 whose outer shell is a cylindrical body, and in the front part of the shield frame 3, an excavation room 7 and a machine room 8 are partitioned by a partition wall 9. A plurality of cutter blades 10 are provided at the front of the excavation chamber 7.
A cutter 4 having a rotary shaft 11 is rotatably provided. A rotary shaft 11 of the cutter 3 extends through a partition wall 9 into a machine room 8 and is decelerated by a drive device 12 provided in the machine room 8. It is connected via the machine 13.

In the machine room 8, a screw conveyor 14 for carrying out the earth and sand in the excavation room 7 is provided, and the screw conveyor 14 has a carry-in end portion formed in the partition wall 9 to carry out the earth and sand discharge port 15 (see FIG. 2). (Also shown in FIG. 2), and at the other end extending obliquely upward and rearward from this, an outlet 16 for discharging earth and sand is formed so as to be openable and closable, and a screw drive device 17 is provided. A shield jack 18 for advancing the shield frame 3 is provided at the rear of the machine room 8 so that the shield frame 5 can be expanded and contracted. The shield frame 5 excavates the ground in front while rotating the cutter 4. At the same time, the extension of the shield jack 18 allows the forward movement. A machine-folded jack 19 for changing the moving direction of the shield frame 3 is provided in the machine room 8. The machine-folded jack 1
9 is adapted to change the moving direction of the shield frame 3 by being intermittently extended in association with the rotation of the cutter 4.

Behind the shield frame 3, a plurality of divided segments 20 that form a tunnel wall are arranged along the inner circumference of the excavated tunnel. The segment 20 is arranged by an erector 21 rotatably provided in the machine room 8. The erector 21 is provided on the outer peripheral end of a rotatable frame 22 that is connected to a drive device (not shown) in the machine room 8. The erector 22 is extendable and retractable. Segment support arm 23
The segment support arm 23 holds the segment 20 and moves along the inner circumference of the tunnel to transfer the segment 20 to a desired position on the inner circumference of the tunnel.

Reference numeral 24 denotes a tail seal, which seals between the rear end of the shield frame 3 and the segment 20 to prevent groundwater and the like from flowing into the tunnel.

By the way, as shown in FIG. 2, a cylindrical body 6 is fitted around the outer periphery of the front end portion of the shield frame 3 in the excavation direction so as to extend forward from the cutter 4. For example, when joining a tunnel under excavation to an existing tunnel 2, the tubular body 6 is extended forward by extension of the center-folding jack 19 and the joining portion 5 between the tunnels is joined as shown in FIG. It surrounds the natural ground and prevents landslides at the joint 5.

Further, an expandable and retractable excavating bit 25 for excavating the natural ground along the extending direction of the cylindrical body 6 is provided at the outer peripheral end of the cutter 4.

In this embodiment, as shown in FIG. 3, the drill bit 25 includes a support frame 26 fixed to the tip of the cutter 4.
It is provided in a retractable manner via a support cylinder 27, and its base is connected to a jack 28 provided in the support frame 26. The jack 28 is, for example, a hydraulic jack (hydraulic or hydraulic) or a mechanical jack (screw jack). Drill bit 25 is cutter 4
While rotating integrally with the cylinder body 6, the hole 29 opened in the cutter 4 from the inside of the support frame 26 is inserted, and the cylinder body 6 is extended obliquely outward in the radial direction thereof, that is, toward the tunnel 2 to be joined. The ground is excavated along the extension direction of. The hole 29 may be provided on the side of the cutter 4 so that the excavating bit 25 can be extended from this.

Further, reference numeral 30 in the figure is a copy cutter for digging the inner circumference of the tunnel.

Next, the operation of the above embodiment will be described.

The shield machine 1 excavates the natural ground to form a tunnel while advancing to form a tunnel, and arranges segments 20 along the inner peripheral surface of the tunnel to form a tunnel.

When joining the tunnel under excavation to the existing tunnel 2, for example, as shown in FIG.
The shield machine 1 is stopped in front of, and as shown in FIG. 3, the cutter 4 is rotated while extending the excavation bit 25 toward the existing tunnel 2. Thereby, the cylindrical body 6
In the extending direction of the cylinder, that is, along the extending track of the cylinder between the cylinder and the buried object such as the existing tunnel, the ground excavation is performed, and the resistance when the cylinder 6 extends is greatly reduced. Can be extended and the extension can be facilitated.

Further, since the excavating bit 25 is expanded and contracted obliquely outward in the radial direction of the cutter 4, the excavated earth and sand enter the excavation chamber 7 by its own weight, which facilitates excavation.

Further, since the support frame 26 supporting the excavation bit 25 stirs the excavated soil in the excavation chamber 7 as the cutter 4 rotates, the excavated soil can be easily discharged.

The shape of the existing tunnel 2 to be joined is, for example,
In the case as shown in FIG. 1, the expansion / contraction of the excavation bit 25 may be appropriately operated to prevent the excavation bit 25 from colliding with the existing tunnel 2.

Further, in the above-described embodiment, the excavation bit 25 is expanded and contracted toward the cutter 4 in the diagonally outward and outward direction, but the invention is not limited to this, and may be expanded and contracted horizontally and forward.

[Advantage of the Invention] According to the present invention, when a tunnel under excavation is joined to an existing tunnel, for example, the excavation bit excavates the natural ground along the extending direction of the cylinder, so that the cylinder extends. The resistance at the time is reduced and the extension is easy.

[Brief description of drawings]

FIG. 1 is a side sectional view showing an embodiment of the present invention, and FIG.
FIG. 3 is an enlarged side sectional view showing a main part, and FIG. 4 is a side sectional view showing a conventional example. In the figure, 1 is a shield machine, 3 is a shield frame, 4
Is a cutter, 6 is a cylindrical body, and 25 is an excavating bit.

Claims (1)

[Scope of utility model registration request] 1. A tubular body is slidably inserted forward from the rotary cutter on the outer periphery of a shield frame having a rotary cutter at the front end in the excavation direction, and the tubular body is an existing tunnel in the excavating direction. In a shield excavator designed to be moved to the buried object side, the earth and sand between the cylindrical body and the existing buried object such as the existing tunnel are extended around the outer peripheral portion of the rotary cutter. A shield machine, wherein a drill bit is provided so as to be capable of expanding and contracting in a diagonally outward and forward direction of the rotary cutter so as to be excavated along.