JPH0417667Y2 - - Google Patents

Description

[Detailed description of the invention] "Industrial application field" This invention relates to a mud water injection device for a shield tunneling machine.

``Prior art'' In conventional shield excavators, the peripheral wall of the shield tube in the excavation chamber is provided with an open end of a viscosity imparting liquid or muddy water injection pipe for injecting viscosity imparting liquid or muddy water into the excavation chamber. Excavated soil from the excavation chamber is press-fitted into the injection pipe from the opening end, clogging the opening end and the injection pipe, making it difficult to convey viscosity-imparting liquid or muddy water, and causing defects that tend to impede excavation work. It was hot. Further, in such a case, even if water is fed at high pressure from the muddy water injection pipe, the face surface holding pressure is applied inside the excavation chamber, so that the earth and sand stuck in the injection pipe cannot be easily discharged.

``Problems to be solved by the invention'' The present invention deals with a situation in which face holding pressure is applied inside the excavation chamber when a clogging phenomenon occurs in the mud water spout and mud water pipe drilled in the peripheral wall of the excavation chamber of the shield tube. The object of the present invention is to provide a muddy water injection device that can quickly eliminate clogging phenomena.

``Means for solving the problem'' The present invention is equipped with an excavation chamber at the front of the shield tube through a sealed wall, and has a rotary cutter at the front of the excavation chamber.
A shield excavation in which a mud water pipe is piped from the rear of the sealed wall along the outer surface of the shield tube to the front end of the shield tube, and a mud water spout that communicates with the mud water pipe is opened on the inner surface of the front end of the tube. In the machine, the front end of a drain pipe is connected to the front end of the mud water pipe, and the rear end of the drain pipe is opened into the shield cylinder, and the mud water spout is placed on the front end side of the drain pipe. It is composed of a mud water injection device in a shield excavator, which is connected to the drain pipe and has an on-off valve in the drain pipe.

``Operation'' Therefore, the shield tube 1 is propelled into the ground, the rotary cutter 4 is rotated, the face surface is excavated by the cutter 4, the on-off valve 8 of the drain pipe 6 is closed, and the mud water is drained from the mud water pipe 5. When the water is sent, the muddy water flows through the mud water pipe 5.
It bypasses the front end of the drain pipe 6 and enters the front end side of the drain pipe 6, and is further jetted into the excavation chamber 3 from the mud spout 7, where it mixes with the excavated earth and sand at the face in the same chamber 3. If the excavated soil in the excavation chamber 3 is forced into the drain pipe 6 from the spout 7 and the spout 7 is clogged, open the on-off valve 8 and, in this state, apply high pressure from the mud water pipe 5 side. When water is supplied, high-pressure water bypasses the front end of the mud water pipe 5 and flows into the drain pipe 6 whose pressure is lower than the pressure inside the excavation chamber 3.
The high-pressure water flows out to the side, and the high-pressure water discharges the clogged earth and sand in the drain pipe 6 to the on-off valve 8 side of the drain pipe 6, thereby eliminating the clogging phenomenon. After removal, the on-off valve 8 is closed, and the mud water is sent from the mud water pipe 5 in the same manner as described above, and the mud water is spouted from the spout 7 into the excavation chamber 3.

"Example" A sealing wall 2 is installed at the front of the underground thrust propulsion shield tube 1.
An excavation chamber 3 is provided through the excavation chamber 3, and a rotary cutter 4 for face excavation is provided at the front of the chamber 3 to form a shield excavator. Then, the slurry water pipe 5 and the drain pipe 6 that are piped inside the rear shield cylinder 1 of the sealing wall 2 are passed through the outer surface of the cylinder 1, and the pipes are extended to the front end of the cylinder 1 along the outer surface. death,
The drain pipe 6 is connected to the outer surface of the front end of the cylinder 1 and connects the front ends of the two pipes 5 and 6 in communication.
A muddy water spout 7 is communicated with the front end of the shield tube 1, and the mud water spout 7 is opened on the inner surface of the front end of the shield cylinder 1. The inside of the excavation chamber 3 is filled with a mixture of excavated earth and sand on the face surface and the muddy water, and internal pressure (so-called face holding pressure) is generated by the propulsion pressure of the shield tube 1 and the muddy water pressure, and the face surface is maintained by the mixture. Retained. If excavated soil is forced into the spout 7 and a clogging phenomenon occurs, water is sent at high pressure from the mud water pipe 5 side and when the on-off valve 8 of the drain pipe 6 is opened, the high pressure water passes through the drain pipe 6 to the low pressure side. ejects into the shield cylinder 1 of
The earth and sand clogging the spout 7 is discharged from the drain pipe 6 into the shield cylinder 1 together with the high-pressure water. Furthermore, when the on-off valve 8 is closed, high-pressure water is spouted from the spout 7 into the excavation chamber 3, and muddy water is continuously supplied into the excavation chamber 3. Then, it is possible to return to normal operation using the mud water supply. In the figure, 9 indicates the rotating shaft of the rotary cutter 4, 10 the bearing thereof, 11 the reduction gear housing, 12 the prime mover, 13 the arm of the rotary cutter 4, and 14 the bit protruding from the front surface of the arm 13. , 15 is a bit protruding from the front end of the rotating shaft 9;
16 is an on-off valve for the mud water pipe 5.

``Effect'' Since this project is configured as described above, the shield tube 1
In the excavation chamber 3 where face surface holding pressure is applied, even if excavated soil is forced into the mud water spout 7 and the mud water spout 7 and both pipes 5 and 6 are clogged, the drain pipe 6 on-off valve By opening 8 and sending high-pressure water from the mud water pipe 5 to the drain pipe 6 side communicating with the low-pressure shield cylinder 1, the clogged earth and sand can be quickly sucked and discharged into the drain pipe 6, and the excavation room Even in a state where the face holding pressure is applied in the 3, there is an advantage that the clogging phenomenon can be quickly eliminated without reducing the holding pressure.

[Brief explanation of drawings]

FIG. 1 is a side view showing the mud water injection device in the shield excavator of the present invention, and FIG. 2 is a bottom view of the mud water pipe and the drain pipe. 1... Shield tube, 2... Sealing wall, 3... Excavation chamber, 4... Rotating cutter, 5... Mud water pipe, 6...
...Drain pipe, 7...Mud water spout, 8...Opening/closing valve.

Claims (1)

[Scope of utility model registration request] An excavation chamber is provided at the front of the shield tube through a sealed wall, a rotary cutter is provided at the front of the excavation chamber, and a mud water pipe is connected from the rear of the sealed wall to the front end of the shield tube along the outer surface of the shield tube. In the shield excavator, the front end of the drain pipe is connected to the front end of the mud water pipe, and the front end of the drain pipe is connected to the front end of the mud water pipe. Open the rear end of the drain pipe into the shield cylinder,
A mud water injection device for a shield excavator, wherein the mud water spout is communicated with the front end of the drain pipe, and the drain pipe is provided with an on-off valve.