JPH041158B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a horseshoe-shaped shield excavator suitable for use when excavating a tunnel having a horseshoe-shaped cross section by a shield method.

[Conventional technology]

Conventionally, most tunnels excavated by shield excavators have circular cross sections, and there are several types of shield excavators that can excavate tunnels with horseshoe-shaped cross sections, including manual and semi-mechanical types. ,
However, there was no mechanical digging type with a rotating cutter installed at the front of the shield shell.

[Problems to be solved by the invention] As shown in Fig. 9, a cross section of a plurality of circular tunnels excavated by a circular shield excavator,
In the case of this circular tunnel, an unnecessary cross section is created in the lower part of the tunnel, and the amount of excavation, waste soil disposal, invert concrete 17, etc. is large, making it uneconomical. This problem becomes more noticeable as the cross section becomes larger.
12' is a circular segment, 15 is concrete roadbed, and 16 is a construction limit.

For this reason, there has recently been a strong demand for tunnels with a horseshoe-shaped cross section, especially in subways, underground passages, and public ditches, and it is desirable to develop a shield excavator that can excavate such horseshoe-shaped tunnels using the shield method. It is rare.

In view of the above-mentioned circumstances, an object of the present invention is to provide a horseshoe-shaped shield excavator that makes it possible to easily excavate a tunnel having a horseshoe-shaped cross section by a shield method.

[Means for solving problems]

To achieve the above object, the present invention includes a horseshoe-shaped outer shell consisting of a substantially flat bottom and an arc-shaped hood connected to both ends thereof, and a horseshoe-shaped outer shell that is arranged to cover the front surface of the outer shell and has a center of rotation. a cutter head, the cutter head being aligned with the center of curvature of the hood portion, and a drive member for reciprocally rotating the cutter head, the cutter head being constantly aligned with the periphery of the hood portion;
an arc-shaped first circumferential edge having a circumference shorter than that of the hood; and second and third circumferential edges extending substantially linearly from both ends of the first circumferential edge toward the center of the bottom at an intermediate position of the reciprocating rotation and connected to each other. The second and third peripheral edges are configured to be aligned with the bottom at the terminal position of the reciprocating rotation.

[Effect]

When the cutter head rotates back and forth, its first circumferential edge is always aligned with the circumferential edge of the hood part, and the second and third circumferential edges are aligned with the bottom at the end of rotation, so that the cutter head allows the cutter head to have the same shape as the horseshoe-shaped outer shell. A tunnel is excavated.

〔Example〕

As shown in FIGS. 1 and 2, the shield excavator has a horseshoe-shaped outer shell 1, and this outer shell 1 consists of a flat bottom part 2 and an arcuate hood part 3 connected to both ends thereof. A cutter head 5 is arranged so as to cover the front surface of the outer shell 1, and its drive shaft 6 is pivotally supported by a partition wall 4 provided inside the outer shell 1. In this embodiment, the support method of the cutter head 5 is an intermediate support method.
The drive shaft 6 has a cylindrical shape, and its rotation center 7 coincides with the center of curvature of the hood portion 3. Drive shaft 6
A ring gear 8 is fixed to the base end of the ring gear 8, and a pinion 10 provided on the shaft of a drive motor 9 is attached to the ring gear 8.
are engaged, and the cutter head 5 is rotated reciprocally as shown in the directions of arrows A and B in FIG. 2 by the operation of the drive motor 9. 11 is the propulsion jack;
12 indicates a horseshoe-shaped lining segment.

The outline of the cutter head 5 is formed by a first circumferential edge 5a and second and third circumferential edges 5b, 5c, and the first circumferential edge 5a is always aligned with the circumferential edge of the hood part 3 and has a shorter circumference than the hood part 3. It has an arc shape. The second and third peripheral edges 5b and 5c are cutter heads 5
At the intermediate position (FIG. 2), they extend linearly from both ends of the first peripheral edge 5a toward the center of the bottom portion 2 and are connected to each other. And the cut head 5 is arrow A, B
It rotates reciprocatingly in the direction and reaches its terminal position (Figures 3 and 4).
When the second and third peripheral edges 5a and 5b reach the bottom 2, the second and third peripheral edges 5a, 5b are aligned with the bottom 2.

The cutter head 5 has a face plate structure in this embodiment, and has a number of bits 13 on its surface and a number of slits 14 for taking excavated earth and sand into the cutter head 5.

In the shield excavator having the above configuration, the cutter head 5 is reciprocated by the drive motor 9 in the directions of arrows A and B as shown in the third and fourth figures, and at this time the outer shell 1 is propelled by the propulsion jack 11. When a predetermined excavation pressure is applied to the tunnel, the face of the tunnel is cut by the bit 13, and the cross-sectional shape of the tunnel is the same as that of the outer shell 1, as shown in FIG.
The shape is the same as that of a horseshoe.

The cutter head 5 is not limited to a face plate structure, but may have a spoke structure as shown in FIG. 5, and in this case, the tips of each spoke that align with the periphery of the hood portion 3 substantially form the first periphery. become. Further, the support method for the cutter head 5 is not limited to the intermediate support method, but may be a center shaft method as shown in FIG. 6 or a peripheral support method as shown in FIG.

〔Effect of the invention〕

As described above, according to the present invention, a horseshoe-shaped tunnel can be excavated using a mechanical shield excavator equipped with a cutter head that rotates back and forth, thereby minimizing wasted space required for tunnel excavation. This allows for economical construction.

[Brief explanation of drawings]

Fig. 1 is a longitudinal sectional side view showing one embodiment of the present invention, Fig. 2 is a front view of the same as above, Figs. 3 and 4 are front views showing reciprocating rotation of the cutter head, and Fig. 5 shows another embodiment. 6 and 7 are longitudinal sectional side views showing further embodiments, FIG. 8 is a longitudinal sectional front view of a tunnel excavated by the shield excavator of the present invention, and FIG. 9 is a conventional shield excavator. Vertical front view of the tunnel excavated by. 1... Outer shell, 2... Bottom, 3... Hood part, 4
...Partition wall, 5...Cut head, 5a...First peripheral edge, 5b...Second peripheral edge, 5c...Third peripheral edge, 6...
...Drive shaft, 13...Bit, 14...Slit.

Claims (1)

[Claims] 1 A horseshoe-shaped outer shell consisting of a nearly flat bottom and an arc-shaped hood connected to both ends, and a horse-shoe-shaped outer shell arranged to cover the front surface of this outer shell, with the center of rotation coinciding with the center of curvature of the hood. the cutter head, and a drive member for reciprocating the cutter head, and the cutter head is always aligned with the circumferential edge of the hood portion, and has an arcuate first circumferential edge having a shorter circumference than the hood portion, and an intermediate position of the reciprocating rotation. A contour is formed by second and third peripheral edges that extend substantially linearly from both ends of the first peripheral edge toward the center of the bottom and are connected to each other, and at the terminal position of the reciprocating rotation, the second and third peripheral edges A horseshoe-shaped shield excavator configured to align with the bottom.