JPH0449274Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a small-diameter tunnel excavation machine, and more specifically, to a tunnel excavation machine equipped with a jet pump for transporting excavated earth and sand.

[Conventional technology]

Conventionally, tunnel excavators, as shown in Figure 1,
Cutting disk 2 rotating to excavate face 1
A cutter chamber 3 is formed on the back side of the cutter chamber 3, and excavated soil 5 lifted up by the rotation of a bucket 4 fixed to the cutter disk 2 is thrown into a hopper 6 provided below in the cutter chamber 3. The earth and sand accumulated in the hopper 6 is then loaded onto a belt conveyor 7 or the like and carried out to the rear outside the machine.

When such a tunnel excavator 8 excavates a face 1 without spring water, the excavated earth and sand 5 generates dust, worsening the working environment, and the cutter disc 2
Since the cutter 9 attached to the cutter chamber 3 also generates heat, water may be separately injected into the cutter chamber 3 to prevent dust and cool the cutter.

However, this water mixes with the excavated earth and sand, resulting in the transported earth and sand becoming a solid-liquid mixture, and since it is difficult to suppress this in a face where there is a lot of spring water, the excavated earth and sand becomes fluidized. When such a solid-liquid mixture is placed on a belt conveyor, excavated soil flows backwards or slides down on the belt conveyor, gets caught in the belt pulley, thickens the belt pulley, increases belt tension, and causes the conveyor belt to break, etc. The disadvantage is that accidents occur.

Unlike the above-mentioned belt conveyor, when excavated earth and sand are transported by a screw conveyor 10 as shown in FIG. 2, the cutter chamber 3 has a watertight structure. However, when transferring from the screw conveyor 10 to a belt conveyor (not shown) behind the excavator 8, the same drawbacks as described above occur.

In the mud water pressurizing type shield excavator 11 shown in FIG. 3, a water supply pipe 12 and a mud removal pipe 13 are installed above and below a cutter chamber 3 having a watertight structure, respectively, and a centrifugal pump 33 or the like is used to pump excavated earth and sand in a solid-liquid mixed state. ,
It is now being ejected outside the aircraft. In such a cutter chamber 3 of the excavator 11, when air is sucked in through the suction port 13a of the mud removal pipe 13 during fluid transport by the centrifugal pump 33, the pump performance deteriorates significantly, making it impossible to transport the mud, resulting in a solid-liquid mixed state. There is a problem in that the excavated earth and sand stagnates inside Katsutachiyamba 3.

In addition, since the suction force (degree of vacuum) of the centrifugal pump 33 is low, if the distance from the suction port 13a to the pump 33 is long, it is necessary to prevent suction from becoming impossible. For that purpose, Katsutachiyamba 3
It is necessary to maintain water pressure, and a structure with high pressure resistance is required.

[The problem that the idea aims to solve]

In either case, if the outside diameter of the excavator itself is small, it is difficult to secure a wide bottom area for the hopper, and it is also difficult to use a conveyor that carries out the earth and sand with a large diameter and width. I'm in a situation where I can't.

In particular, recently, in the field of tunnel boring machines, TBM (tunnel boring machine), which can ensure economic efficiency with the minimum necessary excavation diameter, has been
machine) is expected to emerge. In this case,
Due to the size of the equipment and work space used to extract excavated earth and rock (sludge), the lower limit of diameter reduction is limited to a diameter of 2.6 m at most, making it possible to create tunnel excavators with even smaller diameters. Various studies have been conducted for this purpose.

On the other hand, when the excavator is transferred from the above-mentioned belt conveyor to the unloading trolley at the rear of the excavator and transported out of the tunnel, the laid rail must be made into a single track, and the excavation work must be carried out in consideration of the waiting time for the empty trolley. Must be done intermittently. Also, consideration must be given to traffic safety in Trotsko.

By the way, Utility Model Application Publication No. 53-129136 and Utility Model Application Publication No. 55
Publication No. 71792 describes a so-called mud water pressure shield type excavator in which the inside of the cutting chamber is constantly pressurized with mud water. In this case, the pressure inside the cutter chamber is used to carry out the excavated waste along with the mud water through the mud removal pipe.

In this type of excavator, it is necessary to pressurize the inside of the cutting chamber with muddy water, and water loss prevention equipment such as segments and tail seals is required to prevent water loss to the rear. Therefore, the segment and segment construction costs increase, and it becomes impossible to adopt a flexible work style in which the use of segments can be changed as appropriate depending on the situation of the ground.

On the other hand, Japanese Unexamined Patent Publication No. 56-48500 describes a shield construction method using a jet pump. According to this, work efficiency is improved in various aspects,
In addition, its continuous operation shortens the construction period and reduces construction costs. However, it requires an atmospheric air introduction pipe to the protective pipe connected to the jet pump, and the jet pump also requires a long suction pipe, which increases the suction resistance. the result,
Pump performance is severely hampered by suction resistance, and there is a problem that maximum efficiency cannot be achieved.

On the other hand, in developing a small-diameter tunnel excavator like the one mentioned above, it can be said that the use of a jet pump is extremely effective, but it is important to know how well the pump equipment for transporting gravel can be installed inside the machine. The big challenge is how to arrange it and make it function efficiently. From this point of view, with the jet pump equipment mentioned above, it is not possible to continuously carry out the waste during excavation to the outside of the machine, along with dust, air, and spring water. Improvements are needed in this area.

The present invention was made to solve the above-mentioned problem, and its purpose is to remove excavated earth and sand from a tunnel excavator or shield excavator (hereinafter referred to as a tunnel excavator). The hopper and jet pump in the hopper must be able to smoothly and continuously carry out the excavated soil together with dust, air, and spring water to the outside of the machine without stagnation of the excavated soil in a solid-liquid mixed state inside the hopper. In addition, the arrangement of the material intake port can be selected to maximize the soil discharge efficiency, the suction resistance can be minimized to maximize pump efficiency, and the soil discharge mechanism including a hopper and jet pump can be selected. The jet pump itself can be made smaller, the pump performance remains the same even when air is sucked in at the output intake port of the jet pump, there is no need to control the water level or water pressure at the face, and when it is necessary to prevent face collapse, it is possible to apply water pressure to the cutaway chamber. The katsutachiyamba can be made into a watertight structure so that it can be hung.
There is no need for equipment to prevent water leakage to the rear, and there is no need for segments. Therefore, depending on the ground conditions, it is possible to request without music, and segment costs can be reduced. The purpose of the present invention is to provide a small-diameter tunnel excavator that achieves this.

[Means to solve the problem]

This invention is applied to a tunnel excavator in which a hopper is installed in the cutter chamber to collect earth and sand excavated by rotation of the cutter disk, and the earth and sand in the hopper is carried out by water flow. be done.

Its feature is that, as shown in FIGS. 4 to 6, a jet pump 24 is disposed at the bottom 6a of the hopper 6. A discharged material intake port 26 provided downstream of a nozzle 29 for accelerating water flow in the jet pump 24 is opened to communicate with the bottom 6a of the hopper 6. And the pump 27 at the rear of the excavator
By increasing the speed of pressurized water supplied from the pipe 28 through the nozzle 29, the output material intake port 26
Negative pressure is generated at the throat 30 near the hopper, and the excavated earth and sand 5 in the hopper 6 is sucked together with dust, air, and water by the water flow of the negative pressure, and the earth and sand 5 is carried out of the machine by the water flow. The casing 25 is provided to reduce the size of the entire fuselage.

[Effect]

Accumulation of the excavated earth and sand 5 into the hopper 6 is performed by a bucket 4 which is fixed to the cutter disk 2 and rotates. The excavated soil 5 accumulated in the hopper 6 is
A solid-liquid mixture is created by spring water or jet water. On the other hand, pressurized water is supplied from a pump 27 at the rear of the excavator via a pipe 28. The pressurized water is accelerated by passing through the nozzle 29 and creates a negative pressure at the throat 30 near the output intake 26 . Due to the negative pressure water flow, the excavated earth and sand 5 in the hopper 6 are transported to the casing 25 along with dust, air, and water.
The earth and sand 5 are carried out by the water flow and carried out of the machine.

In this case, even if there is air in the vicinity of the discharged material intake port 26, there is no effect on the suction and discharge capabilities of the jet pump 24, and normal discharge can be ensured. That is, regardless of the amount of accumulated excavated earth and sand 5, spring water, jet water for purposes such as cutting cutlet cooling, air, etc. in the cutter chamber 3, after they are accumulated in the hopper 6, they are pumped from the bottom 6a of the jet pump 24. Due to the suction force, the material is sucked in from the output material intake port 26 and continuously sent out.

[Effect of idea]

According to the present invention, when carrying out the excavated earth and sand in the hopper outside the machine, the excavated earth and sand in a solid-liquid mixed state in the hopper can be smoothly discharged outside the machine without stagnation. Compared to conveying excavated soil using a conventional belt conveyor or pressurizing mud water, the earth and sand conveying mechanism itself, including not only the hopper but also the jet pump, has been made smaller.
The overall size of the aircraft will be reduced.

The arrangement of the hopper and jet pump in the cutter chamber, as well as its discharged material intake port, can be selected to maximize sediment discharge efficiency, eliminating the need for incidental elements such as an atmosphere introduction pipe, and eliminating the need to provide a long suction pipe for the jet pump. Even when air is sucked in through the output intake port of the jet pump, the pump performance remains the same, and the suction resistance can be minimized to maximize pump efficiency.

In addition, in the case of a pressurized mud water type, if air is sucked in at the suction port, the pump performance will drop significantly, making it impossible to carry out the earth and sand, so it is necessary to control the water level and water pressure at the face to prevent air suction. When using a pump, the performance of the pump remains unchanged even when air is sucked in at the material intake port, and there is no need to control the face water level or water pressure. Furthermore, when there is no need to apply water pressure to the cut chamber, the mechanical strength and sealing ability of the cut chamber can be reduced.

In addition, since a jet pump is installed,
If the katsutachi yamba has a watertight structure and it is necessary to prevent the face from collapsing, water pressure can be applied to the katsutachi yamba, and if necessary, sufficient water can be used to prevent dust from scattering and to cool the katsutachi. However, there will be no problem in carrying out the earth and sand. Furthermore, since there is no need to pressurize the interior of the Katsutachiyamba with muddy water, there is no need for equipment to prevent water from flowing backwards, and there is no need for segments, so it is possible to This enables segment cost savings and offers many advantages over traditional tunnel boring machines and shield boring machines.

〔Example〕

EMBODIMENT OF THE INVENTION Below, this invention is demonstrated in detail based on the drawing which shows the Example.

FIG. 4 is an overall sectional view of a tunnel excavator 20 that uses a jet pump to transport excavated earth and sand.
The cutter disk 2 equipped with an appropriate number of cutters 9 for excavating the face 1 is connected to the transmission gears 21 and 22.
It is rotated by a drive motor 23 via.

A cutter chamber 3 is formed on the back of the cutter disk 2, and a hopper 6 is used to collect earth and sand excavated by the rotation of the cutter disk 2 to carry it out.
is located inside and below. A jet pump 24 is disposed at the bottom 6a of the hopper 6, and a casing 25 of the jet pump 24 has a discharged material intake port 26 that communicates with the bottom 6a of the hopper 6.

The jet pump 24 carries excavated earth and sand 5 out of the machine, and its casing 25 is located at the bottom of the hopper 6, and the discharged material intake port 26 is opened upward as described above. This can be taken in by utilizing the weight of the earth and sand 5 in the hopper 6, and it is also considered that the negative pressure of the jet pump 24 can facilitate suction.

In the jet pump 24, water pressurized by a pump 27 shown in FIG.
The excavated earth and sand 5 located at the material intake port 26 becomes dusty and
It is designed to be sucked in along with air and water.

Therefore, the taken-in earth and sand 5 is carried out of the machine by the water flow. In addition, the jet pump 24
As shown in FIG. 6, the planar arrangement of the casing 25 is U-shaped in the lower part of the excavator 20, and the jet pump action is carried out by the cutter chamber 3.
It is set up so that the water flow moves from the side toward the rear of the aircraft, as shown in the diagram. Note that cooling water to the cutter 9 can also be taken from a pipe 31 branched from the pipe 28.

According to the configuration described above, the operation can be performed as follows.

As shown in FIG. 4, excavated earth and sand 5 is accumulated in a hopper 6 by a bucket 4 which is fixed to a cutter disk 2 and rotates. The accumulated excavated soil 5 becomes a solid-liquid mixture due to spring water or jet water, and is taken into the casing 25 of the jet pump 24 at the discharged material intake port 26, and is smoothly carried out of the machine by riding the water flow. will be transported to. in this case,
Even if there is air in the vicinity of the discharged material intake port 26, there is no effect on the suction and discharge capabilities of the jet pump 24, and normal discharge can be ensured.

Incidentally, the material intake port 26 only needs to have a hole larger than the size of the excavated soil 5, and as a result, not only the hopper 6 but also the soil transport mechanism itself including the jet pump 24 can be downsized, and the An excavator with a small diameter can perform its functions without taking up a large space.

In the past, reducing the diameter was severely restricted due to the size and work space of the shedding equipment, but the minimum diameter has been changed from 2.6 m to 2.0 m, which is the minimum diameter necessary for the final purpose of tunnel use. A small-diameter tunnel excavator will be realized. By this,
By minimizing the excavation diameter and realizing relatively inexpensive construction, its economic efficiency will be ensured.

With the above configuration and operation, when the excavated earth and sand in the hopper is carried out of the machine, the excavated earth and sand, which is in a solid-liquid mixed state in the hopper, does not stagnate, and the excavated earth and sand can be transported smoothly, including dust, air, and spring water. The earth and sand can be transported to the rear of the machine, and compared to the transport using a wide belt conveyor and the transport of excavated soil using a mud water pressurizing shield excavator as described in the section of the conventional technology, the earth and sand transport mechanism includes not only a hopper but also a jet pump. By reducing the size of the aircraft itself, the overall size of the aircraft can be reduced.

The arrangement of the hopper and jet pump in the cutter chamber, as well as its discharged material intake port, can be selected to maximize sediment discharge efficiency, eliminating the need for incidental elements such as an atmosphere introduction pipe, and allowing the jet pump to be connected to a long suction pipe. Even if air is sucked in through the output intake port of the jet pump without providing a pump, the pump performance remains the same, and the suction resistance can be minimized to maximize pump efficiency.

In addition, in the case of a mud water pressurized shield excavator, if air is sucked in at the suction port, the pump performance will be significantly reduced, making it impossible to carry out the earth and sand, so it is necessary to control the water level and water pressure at the face to prevent air suction. However, when a jet pump is used, the pump performance remains the same even when air is sucked in at the discharged material intake, and there is no need to control the face water level or water pressure. Furthermore, when there is no need to apply water pressure to the cut chamber, the mechanical strength and sealing ability of the cut chamber can be reduced. In addition, by installing a jet pump, the cutter chamber can be made watertight, and if it is necessary to prevent face collapse,
Water pressure can be applied to the cutlet chamber, and even if sufficient water is used to prevent dust from scattering and to cool the cutlet if necessary, there will be no problem in carrying out the earth and sand. Furthermore, since there is no need to pressurize the interior of the Katsutachiyamba with muddy water, there is no need for equipment to prevent water from flowing backwards, and there is no need for segments, so it is possible to (a construction method that does not use segments or shoring) is now possible, reducing segment costs and offering many advantages over conventional tunnel excavators.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of a conventional tunnel excavating machine, Fig. 2 is a longitudinal cross-sectional view of a different conventional tunnel excavating machine,
Fig. 3 is a schematic diagram of the cutting chamber part of a conventional mud water pressurized excavator, Fig. 4 is a longitudinal sectional view of the tunnel excavator of the present invention, Fig. 5 is an enlarged view of the main part of the present invention, and Fig. 6
The figure is a plan view of the piping of the jet pump. 2... Katsuta disc, 3... Katsuta chamber, 5... Excavation soil, 6... Hopper, 6a... Bottom, 24... Jet pump, 25... Casing, 26... Material intake port, 27... Pump ,2
8... Piping, 29... Nozzle, 30... Throat.

Claims (1)

[Claim for Utility Model Registration] A tunnel in which a hopper is provided inside the Katsutachi Yamba to collect the earth and sand excavated by the rotation of the cutter disk, and the earth and sand in the hopper is carried out by water flow. In the excavator, a jet pump is disposed at the bottom of the hopper, and a discharged material intake port provided downstream of a nozzle for accelerating water flow in the jet pump is opened to communicate with the bottom of the hopper, and a jet pump is provided at the bottom of the hopper. By increasing the speed of pressurized water supplied from the pump via piping with the nozzle,
Negative pressure is generated in the throat near the material intake port, and the water flow of the negative pressure sucks the excavated earth and sand in the hopper together with dust, air, and water, and carries the earth and sand on the water flow to the outside of the machine. A small-diameter tunnel excavator characterized by being equipped with a casing for carrying out and reducing the overall size of the machine.