JP2695676B2 - Obstacle cutting equipment of shield excavator - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an obstacle cutting device for a shield excavator.

(Prior Art) In an urban area, foundation piles of an existing building are buried everywhere, and there are cases where the installation locations of these foundation piles are not recorded. Before constructing a tunnel underground in such a place, drilling will be performed at several places from the ground on the planned shield passage, and the soil condition will be surveyed. They often excavate and encounter unexpected and unexpected obstacles. Obstacle removal work in such a case with a shield excavator is usually performed from inside the machine, and before the work, after stabilizing the face by injecting a chemical solution, the cutter head is gradually rotated to adjust the position of the cutter slit in the cutter head. Obstacles are visually cut and removed while changing. All of the cutting and removing operations are performed manually by workers.

(Problems to be Solved by the Invention) As described above, conventionally, when a sudden obstacle is encountered during shield excavation in an urban area or the like, there are the following problems.

(I) Termination of shield excavation necessitates extension of the construction period.

(Ii) The aircraft will be damaged at the time of the encounter, and it will be necessary to investigate the conditions of soil, spring water and obstacles on the face and to take countermeasures.

(Iii) It takes a great deal of time and money to work on the face and to cut and remove obstacles.

(Iv) It is difficult to ensure the safety of workers removing obstacles.

The present invention has been proposed in view of such circumstances, and a purpose thereof is to perform shield excavation in which removal of obstacles encountered during shield excavation is performed safely and easily without stopping the shield machine. An object of the present invention is to provide an obstacle cutting device for a machine.

(Means for Solving the Problems) In order to achieve the above-mentioned object, an obstacle cutting device for a shield excavator according to the present invention includes a rotary driving device on a cutter head portion having a large number of cutter bits arranged on a face plate. A rotary shaft body that is driven to rotate in parallel with the face plate is mounted on the outer peripheral surface of the rotary shaft body. It is characterized by having been established.

(Operation) Since the present invention is configured as described above, when encountering a foundation pile which is an underground obstacle during shield excavation, the rotary shaft mounted on the cutter head is rotated by the rotary drive device. Thereby, the reinforcing bar cutting bit and the concrete cutting bit disposed on the outer peripheral surface of the rotary shaft body in the longitudinal direction are projected to the front surface of the cutter head, and the cutter head is driven and rotated in this state, thereby driving the pile reinforcing bar of the foundation pile. And concrete of pile skeleton is cut.

At this time, since the reinforcing bar cutting bit and the concrete cutting bit are arranged with a step, first, the covering concrete portion of the pile reinforcing bar in the foundation pile is cut, and then the pile skeleton concrete and the pile reinforcing bar are cut. Thus, the obstacle can be easily and safely processed from the inside of the shield machine irrespective of human power without performing a face stabilizing operation such as a chemical liquid injection method.

Also, even when the cutting bit is unusable due to wear loss or the like, the rotating shaft can be rotated to move the new cutting bit to the cutting position.

(Example) Hereinafter, the present invention will be described with reference to an illustrated example.

In front of the shield body (1), radially arranged slits (4) (5) are opened to the chamber (6) on the face plate of the cutter head (3) rotated by the drive source (2). On one side of the slit portion (5), a number of cutter bits (7) for cutting excavated earth and sand are provided. Inside the slit portion (4), a box-shaped rotary shaft (8) is rotatably supported between supporting members (3a) and (3b), which are part of the cutter head (3), and the rotary shaft ( A plurality of concrete cutting bits (9) and reinforcing bar cutting bits (10) are alternately arranged on the outer peripheral surface of (8) with a step as described later along the longitudinal direction and fixed. One end of the rotating shaft body (8) is connected to a rotation drive device (12) via a bearing (11) of a support member (3a) of the cutter head (3). (13) in the figure is the leading cutter bit. The excavation of the shield body (1) is performed by applying a reaction force to the segment (15) by a shield jack (14) and moving forward, and rotating the cutter head (3) to cut the earth and sand and cutting the soil (4) (5). , Into the chamber (6), and carried out behind the shield body (1) by the screw conveyor (16).

The rotation shaft (8) is configured to rotate by a drive rotation device (12) engaged so as to be able to rotate forward and reverse, and to rotate to a predetermined position when necessary.

The concrete cutting bit (10) is disposed on three surfaces of the rotating shaft (8), and can be switched in three stages, and a cemented carbide bit (10a) is implanted on the surface of the rotating shaft (8). The cutting bit (10) is fixed, and the height is higher than the cutting bit (9) for the reinforcing bar. The rotating shaft (8)
A leading cutter bit (13) is provided on the remaining one surface. (Refer to FIG. 4) The cutting bit (9) for the reinforcing bar is disposed on four surfaces of the rotating shaft (8) and can be switched in four stages, and a carbide bit (9a) is provided on the surface of the rotating shaft (8). A cutting bit (9) having a cutting edge is fixed at an acute angle with the cutting edge, and protrudes higher than the preceding cutting bit (13). (Refer to FIG. 5.) Normally, cutting of earth and sand is carried out with the cutter bit (7). In parallel with this, the leading cutter bit (13) cuts into the excavation surface in advance, and the excavation by the subsequent cutter bit (7) is performed. For the sake of simplicity, the height of the leading cutter bit (13) is higher than the cutter bit (7). (See FIG. 6.) FIG. 7 shows the relationship between the protruding heights of the respective bits. When a reinforced concrete pile is buried underground in the excavation path of a shield excavator, the pile excavator cannot be passed without removing the obstacle that is an obstacle in front of the shield excavator during excavation. If it is found that there is an obstacle pile in the excavation path, it is necessary to cut it small and remove it. In the case of reinforced concrete piles, the excavator first encounters the concrete layer covering the rebar, and then encounters the pile rebar. Therefore, the protruding height of each bit from the front of the cutter bit of the shield excavator is apparent from Fig. 7. To
The position of the concrete cutting bit (10) is higher first,
Next, the rebar cutting bit (9), and then the leading cutter bit (1)
3), and steps A, B, and C are sequentially added to the cutter bit (7).

Therefore, the excavation of the shield excavator is done by the cutter head (3)
Is driven to cut the obstacle in front of the area where the shield excavator can pass, and the cut pile is taken into the chamber (6) from the cutter slit members (4) and (5),
Normal drilling earth and sand are mixed and discharged to the rear of the shield body by the screw conveyor (16).

When the removal of the obstacle is completed, the rotating shaft (8)
Can be rotated by the drive rotation device (12), and the leading cutter bit (13) can be protruded beyond the cutter head (3) to return to normal shield excavation work.

Even when the excavation bit cannot be used due to wear loss or the like, the rotary shaft (8) is rotated by the rotary drive device (12) to move the cutting bit to the cutting position.

(Effect of the Invention) As described above, according to the present invention, a rotary shaft that is driven to rotate in parallel with the face plate via a rotary drive device is mounted on a cutter head portion having a large number of cutter bits disposed on the face plate. Reinforcement cutting bits and concrete cutting bits are arranged side by side on the outer peripheral surface of the rotating shaft body with a different rotating surface along the longitudinal direction with a step difference, so that the rotating drive device rotates to a predetermined position when necessary. The rotating shaft body is a reinforced concrete pile buried in front of an excavator by cutting concrete and rebar by a concrete cutting bit and a reinforcing bar cutting bit arranged in a row on the outer circumferential surface with a step therebetween. Even if there is, it is possible to respond to immediate removal work without stopping the excavator, a planned construction period is secured, and rebar cutting that is lined up with different rotating surfaces of the rotating shaft body The bit and the concrete cutting bit can be moved to a predetermined position when necessary by the rotation of the rotating shaft driven through the rotary drive even when the bit and the concrete cutting bit cannot be used due to wear, loss, etc. It has the effect of being able to respond immediately.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional side view of a shield excavator equipped with an obstacle cutting device according to the present invention, FIG.
3 is a cross-sectional plan view of a main part of the cutting device, FIG. 4 is a cross-sectional plan view of a concrete cutting bit, FIG. 5 is a cross-sectional plan view of a reinforcing bar cutting bit, FIG. 6 is a cross-sectional plan view of a preceding cutter bit, FIG. The figure is an explanatory view showing the protruding height of each cutter bit. (1) Shield body, (3) Cutter head, (4) Cutter slit section, (6) Chamber, (7) Cutter bit, (8) Rotating shaft body, (9) … Concrete cutting bit, (10)… Rebar cutting bit, (12)… Rotary drive.

Claims (1)

(57) [Claims] 1. A rotary shaft body, which is driven to rotate in parallel with a face plate via a rotary driving device, is mounted on a cutter head portion in which a number of cutter bits are arranged on the face plate, and an outer peripheral surface of the rotary shaft body is An obstacle cutting device for a shielded excavator, wherein a rebar cutting bit and a concrete cutting bit are arranged in a row with different steps in a longitudinal direction.