JP2542051Y2 - Tail sealing device for tunnel excavator - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tail seal device for stopping water between a tail shield provided at the rear of a tunnel excavator and a segment mounted in an excavated tunnel.

[0002]

2. Description of the Related Art As a tunnel excavation method using a tunnel excavator, there is a construction method in which segments are sequentially mounted in an excavated tunnel. In this case, ground water enters the tunnel from between the tunnel excavator and the segment. Therefore, a tail seal device is used in which a tail shield is attached to a rear portion of a tunnel excavator, and a seal member seals a gap between the tail shield and the segment to stop water. For example, as shown in FIG. 1, a wire brush type tail seal device in which a plurality of wire brushes 2 are attached to a tail shield 1 and grease 4 is sealed between an adjacent wire brush 2 and an existing segment 3. As shown in FIG. 2, a rubber seal type tail seal device in which a plurality of L-shaped rubber seals 5 are attached to the tail shield 1, and the end portions of the rubber seals 5 are pressed against the segments 3. Etc. are known.

[0003]

[Problems to be Solved by the Invention] The former tail seal device stops water by opposing the pressurized grease pressure and the ground water pressure (earth pressure), and the pressurized grease pressure exceeds a certain value. Therefore, it is necessary to increase the number of the wire brushes 2 and the number of stages of the grease 4 to counter the high water pressure as the ground water pressure becomes higher. For this reason, in the case of a tunnel excavator that operates in the ground under high water pressure, as shown in FIG. 3, the number of wire brushes 2 increases, the total length L of the tail seal device increases, If the existing segment 3 and the tunnel excavator 6 undergo a large curved displacement at the time of a correction operation or the like, the existing segment 3 and the tail shield 1 interfere with each other, resulting in poor tunnel construction and operation controllability. The latter tail seal device stops water by the repulsive force of the rubber seal 5. If the repulsive force of the rubber seal 5 is increased, it is possible to withstand high water pressure without increasing the number of rubber seals 5, so that the overall length can be shortened. As described above, even when the existing segment 3 and the tunnel excavator 6 are greatly displaced in a curved manner, the interference between the existing segment 3 and the tail shield 1 can be prevented. However, when the repulsive force of the rubber seal 5 is increased, the rubber seal 5 slides on the outer peripheral surface of the segment 3 in a state where the outer peripheral surface of the segment 3 is tightened by a large kinking force. Although the durability of the rubber seal 5 can be improved by increasing the number of the rubber seals 5 without increasing the repulsive force of the rubber seal 5, the entire length of the tail seal device becomes longer as in the case of the former tail seal device, so that the segment and the tunnel can be easily removed. Even when the excavator is greatly displaced, the segment and the tail shield interfere with each other, resulting in poor workability and operation controllability.

Accordingly, an object of the present invention is to provide a tail seal device for a tunnel excavator capable of solving the above-mentioned problem.

[0005]

A tail shield 16 is provided at the rear of a tunnel excavator, and a cylindrical pipe 23 is attached to a rear end inner peripheral surface 21 of the tail shield 16 via a ring-shaped elastic body 22. Has a slightly smaller diameter than the inner diameter of the cylindrical tube 23, and a waterproof seal 25 is attached between the adjacent segments 24.
Is slidably pressed against the inner peripheral surface of the cylindrical pipe 23.

[0006]

[Operation] Water seal 25 attached to segment 24
Is pressed against the inner peripheral surface of the cylindrical tube 23 to seal it.
When the tail shield 16 advances, the inner peripheral surface of the cylindrical tube 23 slides along the water stop seal 25 to stop high-pressure water, and does not damage the water stop seal 25 even if the pressure contact force is large. . Center of tail shield 16 and segment 2
When the center of 4 is eccentric, the elastic body 22 is deformed and the gap between the cylindrical tube 23 and the outer peripheral surface of the segment 24 can be uniformly held in the circumferential direction.

[0007]

As shown in FIG. 4, a front main body 11 having a cutter head 10 and an intermediate main body 12 are swingably connected by a front thrust cylinder 13, and a rear main body 14 is connected to the intermediate main body 12. A tail shield 16 is provided behind the rear main body 14 so as to be swingable by an intermediate thrust cylinder 15, and a flexible cover 17 is provided between the main bodies and between the rear main body 14 and the tail shield 16. A tail shield thrust cylinder 19 is connected between the rear body 14 and the tail shield 16 to form a tunnel excavator capable of sharply excavating. The tail shield 1
6 is a cylindrical shape as shown in FIG.
A cylindrical pipe 23 is attached to the cylindrical pipe 1 via a ring-shaped elastic body 22. The segment 24 is a cylindrical body having a diameter slightly smaller than the inner diameter of the cylindrical pipe 23. The water-stop seal 25 is slidably pressed against the inner peripheral surface of the cylindrical tube 23, and a cable 26 receiving a thrust force such as a wire is connected between the front end of the cylindrical tube 23 and the tail shield 16. I have. The ring-shaped elastic member 22 has a substantially C-shaped cross-section in which ring-shaped front and rear mounting pieces 28 and 29 are integrally formed at both front and rear ends of a cylindrical portion 27, and the front and rear mounting pieces 28 and 29 are tail shields. 16 is attached to the inner peripheral surface 21 at the rear end, and has a hollow chamber 30 between the two, and can be pressurized by supplying air or water into the hollow section 30. As shown in FIGS. 6A and 6B, the water-stop seal 25 is attached to the mounting base 3.
1 and a water stopping portion 32, and the mounting base 31 is sandwiched between annular mounting concave portions 33, 33 formed on the outer peripheral side of the opposing end face of the adjacent segment 24, and the water stopping seal 25 is separated from the segment 24. It has a shape that does not come off and does not break due to sliding.

Next, the operation will be described. Tail shield 16
When the water seal 25 slides to the rear of the cylindrical tube 23, the tail shield 16 is stopped, and a new segment 34 is attached to the front end face of the segment 24 and the water seal 25 is attached at the same time as shown in FIG. . The tail shield 16 is advanced with the excavator, and the cylindrical pipe 23 is slid along the newly installed water seal 25 as shown in FIG. At this time, since the cylindrical tube 23 is pulled by the rope 26 and moves together with the tail shield 16, the elastic body 22 is not elastically deformed in the front-rear direction due to the thrust force acting on the elastic body 22. When the center A of the tail shield 16 and the center B of the segment 24 are eccentric C as shown in FIG. 9, the elastic body 22 is elastically deformed via the water seal 25 and the outer peripheral surface of the segment 24 and the cylindrical tube 23 Since the gap S with the inner peripheral surface is constant in the circumferential direction, it is possible to seal well over the entire circumferential direction.

Next, another embodiment will be described. As shown in FIG. 10, the elastic body 22 has a ring-shaped mounting plate 40.
The annular front and rear rubber pieces 41 and 42 are attached to the cylindrical pipe 23 by burning and flowing.
Is fitted to the annular notch 43 of the tail shield 16 and attached by the front and rear holding plates 44 and 45, and the space between the attachment plate 40 and the annular notch 43 is sealed with a seal material 46. 47 is a through hole for supplying air or water to the hollow chamber 30.

As shown in FIG. 11, the elastic body 22 has a plate shape having a predetermined width and thickness, and both ends in the width direction are attached to the inner peripheral surface 21 at the rear end of the tail shield 16 with a plate 48 and bolts 49. The elastic body 22 is formed by enclosing a pressurized fluid or gas into the hollow chamber 30 through the through hole 47 to expand the front and rear central portions of the elastic body 22. Is attached by baking additional flow, bonding, etc. In this way, the elasticity of the elastic body 22 can be adjusted by adjusting the pressure of the pressure fluid or gas sealed in the hollow chamber 30.

[0011]

[Effects of the Invention] Waterproof seal 2 attached to segment 24
5 is pressed against the inner peripheral surface of the cylindrical tube 23 to seal it, so that when the tail shield 16 advances, the inner peripheral surface of the cylindrical tube 23 slides along the water-stop seal 25 to stop high-pressure water. However, even if the pressing force is increased, the water stop seal 25 is not damaged. Therefore, the total length can be shortened by reducing the number of the water stop seals 25, the high pressure water can be reliably stopped, and the durability of the water stop seals 25 can be improved. When the center of the tail shield 16 and the center of the segment 24 are eccentric, the elastic body 22 is deformed and the gap between the cylindrical tube 23 and the outer peripheral surface of the segment 24 can be uniformly held in the circumferential direction, without impairing the water stoppage. . It is economical because it is not necessary to seal grease or the like under pressure, and the structure is simple.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a conventional tail seal device.

FIG. 2 is an explanatory view of another conventional tail seal device.

FIG. 3 is an explanatory view of a problem with a conventional tail seal device.

FIG. 4 is an overall view of a tunnel excavator equipped with the tail seal device of the present invention.

FIG. 5 is a cross-sectional view of a tail seal and a water stop portion of a segment.

FIGS. 6A and 6B are cross-sectional views of a mounting portion of a water stop seal.

FIG. 7 is an operation explanatory diagram.

FIG. 8 is an operation explanatory diagram.

FIG. 9 is an explanatory diagram of an operation at the time of eccentricity.

FIG. 10 is a cross-sectional view showing another example of the elastic body attaching portion.

FIG. 11 is a cross-sectional view showing another example of the elastic body attaching portion.

[Explanation of symbols]

16 ... tail shield, 21 ... inner peripheral surface of the rear end part, 22 ... elastic body, 23 ... cylindrical pipe, 24 ... segment, 25 ... waterproof seal.

Claims (1)

(57) [Scope of request for utility model registration] 1. A tail shield 16 is provided at a rear portion of a tunnel excavator, and a rear end inner peripheral surface 2 of the tail shield 16 is provided.
1, a cylindrical pipe 23 is attached via a ring-shaped elastic body 22, a segment 24 is made slightly smaller in diameter than the inner diameter of the cylindrical pipe 23, and a waterproof seal 2 is provided between the adjacent segments 24.
5 is a tail seal device of a tunnel excavator in which a water seal 25 is slidably pressed against the inner peripheral surface of the cylindrical tube 23.