JPH01187289A - Shield excavator - Google Patents

Abstract

PURPOSE:To excavate a tunnel of an oval cross section by a method in which expendable cutters are set on the front end side of a skin plate of an oval cross section and turned in the radial direction of the skin plate while being rocked. CONSTITUTION:Arms 22 are radially attached to a rotary shaft 20 set on the long shaft on the front end side of a skin plate 10 of an oval cross section. Similar arms 22 are set in groups in parallel at a given interval along the shaft 20. A cutter rod 24 is attached to each of the arms 22, end a cutter bit 26 is attached to the tip of the rod 24. The bit 26 is designed to be rocked by a rocking jack 27 and also to be expended or contracted by a jack 28 in such a way that the line connecting the tips has an oval form. A motor 32 is driven to turn the shaft 20, and the ground is excavated in an oval form while rocking the bit 26.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a shield tunneling machine, and particularly to a shield tunneling machine capable of excavating an oblong cross section.

(Prior Art) As is well known, there is a shield construction method as a method for constructing subway tunnels, and in this construction method, a shield excavator is used to excavate the tunnel.

There are various types of shield tunneling machines, but generally those with a circular cross section are widely used.

By the way, subway tunnels usually require two rails, one upper and lower, but in this case, excavating and constructing two tunnels separately would be wasteful in terms of land, construction period, and construction cost.

Therefore, it may be possible to excavate a large circular cross section that can accommodate two rails at once, but although this method is slightly advantageous in terms of construction period than excavating them individually, the cross section efficiency is On the contrary, it gets worse.

For this reason, for example, as disclosed in Japanese Patent Laid-Open No. 47-44931, a shield excavator has been proposed that excavates two circular cross sections that overlap each other at once. This type of excavator had the following problems.

(Problems to be Solved by the Invention) In other words, in the shield tunneling machine disclosed in the above-mentioned publication, a cross section obtained by overlapping two circular cross sections can be obtained at once, so the cross section efficiency is improved. Since the segments installed at the rear of the shield excavator after excavation also have overlapping circles, there is a problem in that assembly and production thereof become complicated.

The present invention has been made in view of the above problems, and an object thereof is to provide a shield excavator capable of excavating an oval cross section, which simplifies the assembly and manufacture of segments.

(Means for Solving the Problems) In order to achieve the above object, the present invention provides a cylindrical skin plate with an oval cross section that is open at both ends, and a cutter rotatably installed on the front end side of the skin plate. The cutter device is rotatably driven in the axial direction of the skin plate and includes a plurality of sets of cutter bits that are provided adjacent to each other in the radial direction of the skin plate. Further, each cutter bit is installed so as to be swingable in the radial direction of the skin plate.

Preferably, each of the cutter bits is configured to be extendable and retractable.

(Function) According to the shield excavator having the above configuration, by moving the skin plate forward while rotating the plurality of cutter bits, a tunnel having an oval cross section corresponding to the skin plate is excavated.

In this case, if each cutter bit is configured to be telescopic and rotated with the cutter bit extended only in front of the skin plate, it is possible to form an excavation hole larger than the cross section of the skin plate, making it possible to perform curved construction. becomes easier.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1 to 4 show an embodiment of a shield tunneling machine according to the present invention.

The shield tunneling machine shown in the figure is an example of a Tonosho-type shield tunneling machine in which the present invention is applied. A cutter device 12 is provided.

In this embodiment, the skin plate 10 has an oval cross-sectional shape, and a partition wall 14 is fixedly installed on the front side of the skin plate 10, and the front side of the partition wall 14 serves as an earth pressure chamber 16 filled with excavated earth. There is.

The cutter device 12 has a dosing chamber 1 separated by a partition wall 14.
6, and the bearing 1 is placed on the long sleeve of the skin plate 1o.
A rotating shaft 20 is rotatably supported via a shaft 8 and is installed on a line connecting the tips of the skin plate 10, and a hollow cylindrical arm 2 is radially attached to the rotating shaft 2o.
2.22..., a cutter rod 24 attached to each arm 22, and a cutter bit 26 fixed to the tip of each cutter rod 22.

In this embodiment, six arms 22 are arranged in one set, and a total of five sets of arms 22 are arranged along the axial direction of the rotating shaft 20 at predetermined intervals. The length of the three sets of arms 22 located on the skin plate 1 is
The length of the short axis of o is set to be approximately the same, and the two pairs located at both ends of the long sleeve side are longer than the other three pairs.
The length of is getting shorter. .

Further, each cutter bit 26 has a cutter rod 24 to which the cutter bit is fixed is inserted into the arm 22, and a jack 28 is attached to the rear end of the cutter rod 24.
The cutter bit 26 is configured to be expandable and retractable by driving the jack 28.

Furthermore, each cutter bit 26 is pin-coupled to the rotating shaft 2°, and is connected to a swinging jack 2 mounted on the outer periphery of the arm 22.
7, the skin plate 10 is configured to be swingable in the radial direction.

Note that the member designated by the reference numeral 29 in FIG. 4 is a support member to which both ends of the swinging jack 27 are connected with pins.

The rotational drive mechanism of the rotary wheel 20 has a pair of driven gears 3o and 30 fixedly installed on both sides of an arm 22 located at the center, and is driven by the driven gear 30 and a motor 32 installed behind the partition wall 14. A pair of drive gears 34 and 34 are connected by chains 36 and 36, respectively.

Covers 38 are attached to both sides of the chain 36, one end of which is supported by the partition wall 14.

In addition, a plurality of screw conveyors 40 for discharging excavated earth and sand, whose tips partially enter the soil storage chamber 16, are disposed on the partition wall 14.

In the shield tunneling machine configured as described above, the motor 3
2 to drive each cutter bit 26 onto the skin plate 1.
The ground is excavated by rotating in the axial direction of 0, and the excavated soil is sequentially taken into the earth pressure chamber 16. Excavation is performed by extending a shield jack (not shown), and the soil is taken into the earth pressure chamber 16. The collected earth and sand is discharged to the outside by a screw conveyor 40 while stabilizing the face.

In this case, the cutter bit 26 of the cutter device 12 for excavating the earth is oscillated by the oscillating jack 27, but at this time, the oscillating angle is set within a range where radially adjacent sets do not interfere with each other, Moreover, if the swing angles are set to gradually deviate within each set, it becomes possible to excavate an oval cross section simply by rotating the cutter bit 26.

In this case, the cutter bit 26 is oscillated only in the section where it protrudes in front of the tip of the skin plate 10, and the section where the cutter bit 26 rotates inside the skin plate 10 is perpendicular to the rotation axis 20. It may be controlled to

Furthermore, when excavating another mountain, if the jack 28 is driven to extend the cutter bit 26 only further forward than the tip of the skin plate 10, an excess excavation is created on the outer periphery of the skin plate 10. curved construction becomes easier.

In the above embodiment, the present invention is applied to a Tonosho-type shield tunneling machine, but the present invention is not limited to this and can be applied to other types of shield tunneling machines.

(Effects of the Invention) As explained above in the embodiments, according to the shield excavator according to the present invention, the cross-sectional shape to be excavated is oval, and the cross-sectional efficiency is higher than that of two circular cross-sections overlapped. Although the shape of the segment is slightly reduced, the shape of the segment becomes an elliptical cross section, making assembly and production easier.

Furthermore, by making the cutter bit telescopic and extending it only in front of the skin plate, it is possible to easily secure the extra trench required for curved construction.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional view showing an example of the shield excavator of the present invention, Fig. 2 is a front view of the shield excavator, Fig. 3 is a sectional view of the main part of the cutter bit, and Fig. 4 is the installation of the cutter bit. FIG. 10・・・・・・・・・Skin plate 12...
・・・・・・・・・Cutter device 26・・・・・・・
・・・・・・Cutter bit 27・・・・・・・・・・・・
・Rolling jack 1st convex It) Fig. 2

Claims (2)

[Claims] (1) A shield excavator comprising a cylindrical skin plate with an oval cross section open at both ends, and a cutter device rotatably installed on the front end side of the skin plate, wherein the cutter device A plurality of cutter bits are rotatably driven in the axial direction of the plate and are provided adjacent to each other in the radial direction of the skin plate, and each cutter bit is swingable in the radial direction of the skin plate. A shield excavator characterized by the fact that it is installed. (2) The shield excavator according to claim 1, wherein each of the cutter bits is configured to be extendable and retractable.