JPH0893388A - Method and device for discharging soil - Google Patents

Abstract

PURPOSE: To prevent troubles due to foreign materials in the excavating work of a shield excavating machine. CONSTITUTION: Foreign materials 15 are caught by movable blades rotating around the center of a screw shaft 8 and fixed blades 11 and the rotation of hollow shaft 8' is stopped by sliding of a coupling 13 with a torque limitter. The stopped state is detected by the revolution sensor 14 to inform of the foreign materials 15. A gate positioned in the upstream or the foreign materials caught, a bulkhead gate for instance installed between a chamber and a screw conveyor 5, is closed and the a cover 12 to take it out is opened to remove the foreign materials 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an earth discharging method and an earth discharging device for discharging earth and sand in a chamber of a shield machine by a screw conveyor and a pressure feed pump connected to an earth discharging port of the screw conveyor. is there.

[0002]

2. Description of the Related Art Conventionally, in order to discharge the earth and sand taken into a chamber in a shield machine, the earth and sand in the chamber are carried out by a screw conveyor and a pressure feed pump connected to an earth discharge port of the screw conveyor. Is being done. By the way, in such a shield machine, foreign matter such as large-diameter gravel, steel sheet pile, iron pipe, etc. may be contained in the earth and sand taken into the chamber, and these foreign matter are clogged in the pump. In some cases, the pressure pump was damaged and the work efficiency of the shield machine was reduced. In order to eliminate the adverse effects caused by such foreign matter, Japanese Utility Model Publication No. 60-15838 proposes a coarse solid matter discharging device including a crushing mechanism 100 for crushing foreign matter as shown in FIG. . The crushing mechanism 100 disclosed in this publication has an auxiliary screw 102 provided next to a discharge screw 101 for discharging earth and sand, and foreign matter 103 in the earth and sand is discharged by the discharge screw 101 and the auxiliary screw 102. It is sandwiched between and crushed.

[0003]

However, although foreign matter such as gravel is easily crushed in the crushing mechanism 100, it is difficult to crush foreign matter made of a metal material. Therefore, even if such a crushing mechanism 100 is used, the problem of breakage of the pressure pump cannot be solved.

The present invention has been made in view of the above problems, and is capable of preventing damage to the secondary side pressure feed pump even when foreign matter is mixed in the screw conveyor during the excavation work by the shield excavator. It is intended to provide a soil method and a soil discharging device.

[0005]

That is, the earth discharging method of the present invention is to discharge earth and sand in a chamber of a shield machine with a screw conveyor and a pressure feed pump connected to an earth discharging port of the screw conveyor. In the method
The foreign matter contained in the earth and sand discharged from the chamber is captured on the upstream side of the pressure feed pump, the screw conveyor is stopped when the foreign matter is captured, and then the captured foreign matter is removed. It is a feature.

Further, the earth discharging apparatus of the present invention is an earth discharging apparatus for discharging the earth and sand in the chamber of the shield machine with a screw conveyor and a pressure feed pump connected to the earth discharging port of the screw conveyor. The present invention is characterized in that a foreign matter capturing means for capturing foreign matter mixed in the transported earth and sand is provided on the upstream side of the pressure pump.

[0007]

According to the soil discharging method of the present invention, the foreign matter contained in the soil discharged by the screw conveyor is caught by the foreign matter catching means, and the catching is detected by the detecting means. As a result, before the problem occurs in the pressure pump on the downstream side, the earth discharging operation such as the conveyance by the screw conveyor and, if necessary, the operation of the shield machine as a whole are stopped. Then, the foreign matter can be removed in the operation stopped state, and the earth and sand containing no foreign matter can be discharged to the pressure feed pump.

According to the soil discharging device of the present invention, the foreign matter mixed in the screw conveyor is caught by the foreign matter catching means, and the foreign matter is prevented from being sent to the side of the pressure feed pump to prevent the damage of the pressure feed pump. To be done.

Furthermore, if the earth discharging device of the present invention is provided with a detecting means for detecting that the foreign matter is captured, the detecting means detects that the foreign matter is captured.
Before this foreign matter causes a problem in the pressure pump on the downstream side, the earth discharging operation such as the conveyance by the screw conveyor and, if necessary, the operation of the entire shield machine is stopped. And
The foreign matter can be removed in the operation stopped state, and the earth and sand containing no foreign matter can be discharged to the pressure pump.

As the foreign matter capturing means, a hollow shaft rotatably supported by a screw shaft of the screw conveyor, and a rotor blade provided on the hollow shaft along the axial direction,
By providing a fixed blade provided in the fixed portion so as to be adjacent to this moving blade, the hollow shaft is connected to the screw shaft via a coupling with a torque limiter, and the hollow shaft is sandwiched between the moving blade and the fixed blade. It is possible to use one that captures foreign matter. The foreign matter mixed in the earth and sand is carried by the rotating moving blade to a position in contact with the fixed blade, where it is sandwiched between the moving blade and the fixed blade. In this case, a detecting means for detecting the trapping of the foreign matter is provided, and a rotation detecting sensor for detecting the rotation of the hollow shaft is provided as the detecting means, and the moving blade and the fixed blade sandwich the foreign matter. Thus, it is possible to use a device that detects that the coupling slips and the rotation of the hollow shaft is reduced or stopped.

As the foreign matter capturing means, a hollow shaft rotatably supported by the screw shaft of the screw conveyor, and a rotor blade provided on the hollow shaft along the axial direction,
A fixed blade provided in a fixed portion so as to be adjacent to the moving blade, the hollow shaft is connected to a hollow shaft drive motor with a relief valve or a torque limiter, and is sandwiched between the moving blade and the fixed blade. As a result, it is possible to use one that captures foreign matter. In this case, a detection means for detecting that the foreign matter is captured is provided, and as this detection means, a rotation detection sensor for detecting the rotation of the hollow shaft is provided, and the moving blade and the fixed blade sandwich the foreign matter. A motor that detects that the motor idles and the rotation of the hollow shaft is reduced can be used. By detecting that the rotation of the hollow shaft has decreased and, in some cases, the rotation of the hollow shaft has stopped, the pinching of the foreign matter is detected.

Further, as the foreign matter capturing means, an outer cylinder portion coaxial with the screw shaft of the screw conveyor and rotatable with respect to a fixed portion, a stop blade provided inside the outer cylinder portion, and the screw shaft A moving blade provided to the outer cylinder portion is connected to the fixed portion via a coupling with a torque limiter, and the moving blade and the stop blade are used to trap foreign matter. it can. The foreign matter mixed in the earth and sand is carried to a position in contact with the stopping blade by the rotating moving blade and is sandwiched by the moving blade and the stopping blade. In this case, a detection means for detecting that the foreign matter is captured is provided, and as the detection means for this,
It is possible to use a sensor that includes a rotation detection sensor that detects the rotation of the stop blade, and that detects that the stop blade rotates when the moving blade and the stop blade sandwich a foreign matter. It is possible to detect the pinching of the foreign matter by detecting the rotation of the stop blade.

Further, as the foreign matter capturing means, a fixed screen provided at a connecting portion between the screw conveyor and the pressure pump and a rotary screen provided adjacent to the fixed screen are provided. It is possible to use one in which a foreign matter penetrating the eyes of the rotary screen is held by the fixed screen and the rotary screen. When the foreign matter mixed in the earth and sand penetrates the eyes of the fixed screen and the eyes of the rotary screen, the foreign matter tries to be rotated by the rotary screen, but the rotation of the fixed screen is suppressed. And its rotating screen. In this case, a detection means for detecting that the foreign matter has been captured is provided, and as the detection means therefor, a torque detection means for detecting a torque for rotating the rotating screen or a rotation detecting means for detecting the rotation of the rotating screen. Rotation detecting means is provided, and the fixed screen and the rotating screen hold the foreign matter penetrating the eyes of the fixed screen and the eyes of the rotating screen to prevent the rotation of the rotating screen from being disturbed. It is possible to use a device that detects that the torque has increased or that the rotation of the rotating screen has decreased. By detecting the increase of the torque or the decrease of the rotation, or the stop of the rotation in some cases, the pinching of the foreign matter is detected.

In the soil discharging apparatus of the present invention, if a discharge port for taking out the foreign matter to remove the foreign matter is provided in the vicinity of the foreign matter catching means, it is easy to immediately confirm and take out the foreign matter. . In addition, if a gate is provided upstream from the foreign matter capturing means or the location where the foreign matter is captured,
It is possible to prevent the foreign matter and the earth and sand from being ejected by the earth pressure when the foreign matter is removed by closing the gate.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, specific embodiments of the soil discharging method and soil discharging device according to the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is a vertical sectional view of a shield machine 1 incorporating an earth discharging device according to an embodiment of the present invention. In addition, an enlarged cross-sectional view (partially cutaway) of the rear portion of the screw conveyor 5 in FIG. 1 is shown in FIG. Here, FIG. 2B is a cross-sectional view taken along the line AA of FIG. In the shield machine 1 of this embodiment, the earth and sand excavated by the cutter head 2 provided on the front surface and taken into the chamber 3 are conveyed backward by the screw conveyor 5 driven by the hydraulic motor 4, and further Sediment is carried to the rear of the shield machine by the pressure pump 6 connected to the soil discharge port of the screw conveyor 5 through the lateral hole formed by the segment 7 (the sand discharge route is indicated by an arrow in FIG. 2A). It is.).

In the screw conveyor 5, the screw 9 at the end of the screw shaft 8 is removed,
A hollow shaft 8'is rotatably supported around the part where the screw 9 is removed, coaxially with the screw shaft 8. Around the hollow shaft, three rows of moving blades 10 are fixed at a predetermined interval and fixed in multiple rows (three rows in the example in the figure) along the axial direction. Fixed blades 11 fixed to an outlet cover 12 provided at the outlet of the casing of the screw conveyor 5 are disposed between the moving blades 10 adjacent to each other. The tip portion of the moving blade 10 is bent toward the rotation side as shown in FIG. 2B, which makes it easier for foreign matter to be caught between the moving blade 10 and the fixed blade 11. .

The hollow shaft 8'is connected to the screw shaft 8 via a coupling 13 with a torque limiter at an end position of the hollow shaft, and a casing wall surface adjacent to the coupling 13 has the hollow shaft 8 '. 8 '
A rotation detection sensor 14 for detecting the rotation of is provided.

In such a structure, the chamber 3
If the foreign matter 15 such as an iron pipe is contained in the earth and sand transported from the foreign matter 1, the foreign matter 1 is generated by the moving blade 10 and the fixed blade 11 which are rotated by the drive of the hydraulic motor 4.
5 are clamped as shown in FIG. This is because the foreign matter 15 moves with the earth and sand into the moving blade 10 and the fixed blade 11.
This is because when the foreign matter 15 flows into the portion where the blade is provided, the speed at which the blade 10 rotates in the circumferential direction is faster than the speed at which the foreign matter 15 is conveyed in the direction along the screw shaft 8 together with the earth and sand. , Foreign matter 15 is moving blade 1
Carried by 0, carried to the position of solid wing 11,
This is because it is sandwiched between the moving blade 10 and the solid blade 11.

The moving blade 10 is provided around a rotatably supported hollow shaft 8 ', and the hollow shaft 8'is connected to the screw shaft 8 via a coupling 13 with a torque limiter. , The rotation of the hydraulic motor 4 passes through the coupling 13 with the torque limiter, and the hollow shaft 8 '
To the rotor shaft 10 which is transmitted to the hollow shaft 8 '.
Rotates with the screw shaft 8. And the hollow shaft 8 '
Is rotatably supported, the moving blade 10 and the solid blade 1
When the foreign matter 15 is sandwiched between 1 and 1, the fixed blade 11 does not move, the torque of the moving blade 11 is transmitted to the solid blade 11 via the foreign matter 15, and the resistance from the solid blade 11 becomes larger than the rotational torque of the moving blade 10. Since the coupling 13 with the torque limiter slips, rotation torque transmission of the screw shaft 8 is cut off,
Irrespective of the rotation of the screw shaft 8, the rotation of the hollow shaft 8 ′ is reduced, and in some cases, the hollow shaft 8 ′ is stopped.
It accumulates in a state of being sandwiched between and the solid blade 11.

The rotation of the hollow shaft 8'is always detected by the rotation detecting sensor 1.
Since the rotation of the hollow shaft 8'has slowed down, the rotation detection sensor 14 can detect that the rotation of the hollow shaft 8'has stopped. It can be seen that it is sandwiched between the wing 10 and the fixed wing 11. A person may constantly monitor the display of the number of rotations of the rotation detection sensor 14.

When the foreign matter 15 is detected as described above, the hydraulic motor 4 is stopped. Next, the foreign matter 15 is taken out from the outlet, but normally earth pressure is applied to the inside of the chamber 3 and the screw conveyor 5 during the earth discharging operation. Therefore, immediately after the earth removal is stopped, the outlet cover 12
When you open, it is very dangerous because the earth pressure erupts the earth and sand. Therefore, as shown in FIG. 1, the bulkhead gate 18 provided between the screw conveyor 5 and the chamber 3 is closed. This bulkhead gate 18
If is closed, the earth pressure in the chamber 3 is cut off in the subsequent flow. Here, the screw conveyor 5 and the pressure pump 6
The soil pressure in the screw conveyor 5 can be lowered by slightly operating the above to slightly discharge the earth and sand in the screw conveyor 5. Then, in order to confirm that the earth pressure has decreased, the pressure inspection means 17 inspects the residual pressure of the earth and sand around the foreign matter. Here, if the pressure still remains, the screw conveyor 5 and the pressure feed pump 6 are slightly operated to discharge the soil.

In this way, the earth pressure in the chamber 3 is not applied to the earth and sand in the portion where the foreign matter 15 is sandwiched, and after the residual pressure is released, the outlet cover 12 is shown in phantom lines in FIG. 2 (b). The foreign material 15 is taken out as shown in FIG. By doing so, it is possible to prevent the eruption of earth and sand from the outlet, which is safe. When the foreign matter 15 is taken out, if the gate 16 provided between the screw conveyor 5 and the pressure feed pump 6 is closed as necessary, the foreign matter 15 may be dropped or sent to the pressure feed pump 6. Can be prevented.

As the bulkhead gate 18, for example, the one whose front view (the view seen from the left side of FIG. 1) is shown in FIG. 3 is used. In this bulkhead gate 18, a pair of gate plates 19 and 19 are provided with gate opening / closing jacks 20 and 20.
It is configured to be opened and closed by the. Therefore, when the foreign matter 15 is detected as described above, these gate plates 19, 1
By closing 9 by the gate opening / closing jacks 20, 20, earth pressure in the chamber 3 is prevented from being applied to the earth and sand in the screw conveyor 5.

In this embodiment, the installation interval between the moving blade 10 and the solid blade 11 is set according to the size of the foreign matter 15 to be captured. In other words, the moving blade 1 is designed so as to be able to capture a foreign matter of a size that causes the pressure pump 6 to be clogged and damaged.
The installation interval between 0 and the solid blade 11 is set.

Further, in this embodiment, the magnitude of the set torque of the torque limiter can be changed according to the properties of the earth and sand to be conveyed. For example, if you want to detect foreign matter in the sand that has a large plastic flowability, the set torque may be small or large.If you want to detect a foreign matter in the sand that has a relatively small plastic flowability, set a large torque. Good.

Further, in the present embodiment, the screw shaft 8
Although the hollow shaft 8'and the hollow shaft 8'are rotationally driven by the common hydraulic motor 4, the drive system for rotating the hollow shaft 8'may be provided separately from the drive system for rotating the screw shaft 8. For example, the rotation of the hollow shaft 8'can be performed by a hydraulic motor via a gear, and in this case, the set torque is the relief pressure of the hydraulic motor circuit. In such a structure, when the foreign matter 15 is captured, the moving blade 10 receives a resistance torque from the solid blade 11 via the foreign matter 15, so that rotation from the hydraulic motor is performed by a relief valve or the like provided in the hydraulic motor circuit. The torque transmission is interrupted, the rotation of the hollow shaft 8'is reduced, and in some cases, the hollow shaft 8'is stopped.
When such a configuration is adopted, since the rotation of the screw shaft 8 and the rotation of the hollow shaft 8'are independent, there is also an effect that an optimum rotation speed can be individually selected.

(Embodiment 2) FIG. 4 is an enlarged side view (partially cutaway) of the rear portion of the screw conveyor 5 incorporating the soil discharging device according to another embodiment of the present invention.
Here, FIG. 4B is a partial cross-sectional view taken along the line BB of FIG.

In this embodiment, the screw shaft 8 is not directly connected to the hydraulic motor 4 and rotated as in the first embodiment, but the screw shaft 8 is provided so as to surround the casing of the screw conveyor 5. 4 is rotated by a gear transmission mechanism (not shown). A moving blade 10 is fixed around the rear end of the screw shaft 8 along the axial direction thereof.
Also in this example, each row is provided with three moving blades 10 as shown in FIG. 4 (b). In this embodiment, since the moving blades 10 are arranged so as to be inclined as shown in FIG. 4 (a), the rotation of the moving blades 10 generates a sand / sand conveying force. Further, stop blades 21 are provided in two rows (two sheets) so as to alternate with the moving blades 10. The stop vane 21 is provided on a base portion 22 mainly composed of an outer cylinder, and the base portion 22 is supported by the casing via a coupling 13 with a torque limiter so as to be rotatable coaxially with the screw shaft 8. Then, on the casing side, as shown in FIG.
A rotation detection sensor 14 for detecting the rotation of is provided.

In such a structure, foreign matter 15 is contained in the earth and sand.
In the same manner as in the first embodiment, the blade 10 and the stop blade 2 are included.
The foreign matter 15 is sandwiched between the and 1. Because, as described above, when the foreign matter 15 flows into the portion where the moving blade 10 and the stop blade 21 are provided together with the earth and sand, the foreign matter 15 is conveyed along with the earth and sand in the direction along the screw shaft 8. This is because the rotating speed of the moving blade 10 in the circumferential direction is faster than the rotating speed of the moving blade 10. Therefore, the foreign matter 15 is carried by the moving blade and moved to the position of the stopping blade 21, and the moving blade 10 and the stopping blade 21 cause the foreign matter 15 to move. Because it is sandwiched.

At this time, the torque of the moving blade 10 is transmitted to the stop blade 21 via the foreign matter 15. Here, since the stop blade 21 is rotatably supported by the fixed portion via the coupling 13 with a torque limiter, when the torque is transmitted, the stop blade 21 holds the foreign matter 15 while holding a constant resistance torque. While starting to rotate together with the moving blade 10 and the foreign matter 15. Therefore, the moving blade 10 and the stopping blade 21 catch the foreign matter 15 by pinching the foreign matter 15 while rotating. In this way, the rotation detection sensor 14 can know that the rotation of the base portion 22 has started, and therefore the presence of the foreign matter 15 can be detected.

When the foreign matter 15 is detected as described above, the hydraulic motor 4 is stopped and the bulkhead gate 18 is closed, and the earth pressure inside the screw conveyor 5 is released as in the first embodiment, and the outlet cover is removed. 12 is opened and the foreign matter 15 is taken out.

(Third Embodiment) In the first and second embodiments, the gate 16 is provided on the downstream side of the means for catching (sandwiching) a foreign substance, but in this embodiment, as shown in FIG. In addition, the gate 16 is provided on the upstream side of the means for capturing the foreign matter.

In the embodiment shown in FIG. 5, two fixed screens 23 each of which is composed of three rod-shaped members are provided so as to block the path of earth and sand.
Between the fixed screen 23 and the rotating screen 24
Is provided. The rotary screen 24 also has a sectional shape similar to that of the fixed screen 23, and is rotated by the hydraulic motor 25.

In such a structure, foreign matter 15 is contained in the earth and sand.
, The foreign matter 15 penetrates the eyes of the fixed screen 23 and the rotary screen 24, and the foreign matter 15 is held by the fixed screen 23 and the rotary screen 24. As a result, the retained foreign matter 15
As a result, the rotation of the rotary screen 24 is disturbed, the torque required to rotate the rotary screen 24 increases, the hydraulic pressure of the hydraulic motor 25 increases, and the rotation of the rotary screen 24 decreases or stops. The presence of the foreign matter 15 is detected by the increase in the hydraulic pressure of the hydraulic motor 25 being detected by the hydraulic pressure detector 26.

Although the foreign matter is detected here by the change of the hydraulic pressure, the foreign matter may be detected by providing a rotation detecting sensor for detecting the rotation of the rotary screen 24 and knowing that the rotation is reduced or stopped. . In this case, a torque limiter coupling may be provided between the hydraulic motor 25 and the rotary screen 24.

When the foreign matter 15 is detected as described above, the rotation of the screw shaft 8 is stopped, the gate 16 is closed, and only the pressure pump 6 is slightly operated to release the earth pressure, as in the first embodiment. After that, the outlet cover 12 is opened and the foreign matter 15
Is taken out. In this case, the bulkhead gate 18 is unnecessary.

In this embodiment, the fixed screen 23 and the rotary screen 24 are provided on the downstream side of the gate 16, but they may be provided on the downstream side of the gate 16. In this case, the bulkhead gate 18 is necessary. In addition, in the present embodiment, the fixed screen 23 and the rotary screen 24 are each formed of three rod-shaped portions arranged in parallel, but they may be formed of mesh-shaped or radially arranged rod-shaped portions. .

[0039]

As described above, according to the present invention, it is possible to catch and detect the foreign matter in the earth and sand. Therefore, it is possible to stop the soil discharging operation and take out the foreign matter before the pressure pump is damaged. it can. As a result, it is possible to discharge the earth and sand that does not contain foreign matter, and the foreign matter will not be clogged or damaged in the pump, which reduces the efficiency of excavation work and minimizes the cost of repairing the pump, etc. it can.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a shield machine 1 incorporating an earth discharging device according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a rear portion of the screw conveyor according to the embodiment of the present invention.

FIG. 3 is a front view of a bulkhead gate.

FIG. 4 is a sectional view of a main part of a shield machine according to another embodiment of the present invention.

FIG. 5 is a cross-sectional view of a main part of a shield machine according to still another embodiment of the present invention.

FIG. 6 is a diagram showing a structure of a conventional screw conveyor.

[Explanation of symbols]

 1 Shield Machine 2 Cutter Head 3 Chamber 4 Hydraulic Motor 5 Screw Conveyor 6 Pressure Pump 7 Segment 8 Screw Shaft 8'Hollow Shaft 10 Moving Blade 11 Fixed Blade 12 Outlet Lid 13 Torque Limiter Coupling 14 Rotation Detection Sensor 15 Foreign Material 18 Bulk Headgate 21 Stop Wing 23 Fixed Screen 24 Rotating Screen 25 Hydraulic Motor 26 Oil Pressure Detector

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiroshi Asano 3-1-1 Ueno, Hirakata-shi, Osaka Komatsu Ltd. Osaka factory (72) Masahiro Hatamaki 3-1-1 Ueno, Hirakata-shi, Osaka Company Komatsu Manufacturing Osaka factory (72) Inventor Masao Fukada 3-1-1 Ueno, Hirakata-shi, Osaka Komatsu Manufacturing Osaka factory

Claims (14)

[Claims] 1. A method of discharging earth and sand in a chamber of a shield machine with a screw conveyor and a pressure feed pump connected to an earth discharge port of the screw conveyor, wherein the earth and sand are contained in the earth and sand discharged from the chamber. The soil removal method is characterized in that the foreign matter present is captured on the upstream side of the pressure pump, the screw conveyor is stopped when the foreign matter is captured, and then the captured foreign matter is removed. 2. The earth removing method according to claim 1, wherein a gate provided upstream of a place where the foreign matter is captured is closed when the captured foreign matter is removed. 3. An earth discharging device for discharging earth and sand in a chamber of a shield machine with a screw conveyor and a pressure feeding pump connected to an earth discharging port of the screw conveyor, which conveys to the upstream side of the pressure feeding pump. The soil removing device is provided with a foreign matter capturing means for capturing foreign matter mixed in the soil. 4. The soil discharging device according to claim 3, further comprising detection means for detecting that the foreign matter is captured by the foreign matter capturing means. 5. The foreign matter capturing means includes a hollow shaft rotatably supported by a screw shaft of the screw conveyor, a moving blade axially provided on the hollow shaft, and adjacent to the moving blade. And a fixed blade provided in a fixed portion, the hollow shaft is connected to the screw shaft via a coupling with a torque limiter, and the foreign matter is captured by being sandwiched between the moving blade and the fixed blade. The soil discharging device according to claim 3, wherein 6. Further, a detecting means for detecting that the foreign matter is caught by the foreign matter catching means is provided, and the detecting means is provided with a rotation detecting sensor for detecting rotation of the hollow shaft, and fixed to the moving blade. The earth removing device according to claim 5, which detects that the rotation of the hollow shaft is reduced or stopped due to slippage of a coupling of the blade when the foreign matter is sandwiched between the blade and the blade. 7. The foreign matter capturing means includes a hollow shaft rotatably supported by a screw shaft of the screw conveyor, a moving blade axially provided on the hollow shaft, and adjacent to the moving blade. And a fixed blade provided in a fixed portion, the hollow shaft is connected to a hollow shaft drive motor with a relief valve or a torque limiter, and traps foreign matter by sandwiching between the moving blade and the fixed blade. The earth removing device according to claim 3, wherein 8. A detection means for detecting that the foreign matter is captured by the foreign matter capturing means is provided with a rotation detection sensor for detecting the rotation of the hollow shaft, and fixed to the moving blade. The exhaust according to claim 7, which detects that the rotation torque of the motor is not transmitted to the hollow shaft due to the foreign matter being pinched by the blade and the rotation of the hollow shaft is reduced or stopped. Soil equipment. 9. The foreign matter capturing means includes an outer cylinder portion coaxial with a screw shaft of the screw conveyor and rotatable with respect to a fixed portion, a stop blade provided inside the outer cylinder portion, and the screw shaft. The outer cylinder portion is connected to the fixed portion via a coupling with a torque limiter, and the foreign matter is captured by being sandwiched between the moving blade and the stop blade. The soil discharging device according to claim 3, which is characterized in that. 10. Further, a detection means is provided for detecting that the foreign matter is captured by the foreign matter capture means, and the detection means is provided with a rotation detection sensor for detecting rotation of the stop blade, and the rotary blade and the stop blade are stopped. The earth removing device according to claim 9, wherein the blade detects the foreign matter that is caught by the blade and the coupling slides to rotate the stop blade. 11. The foreign matter capturing means includes a fixed screen provided at a connection portion between the screw conveyor and the pressure feed pump, and a rotary screen provided adjacent to the fixed screen. 4. The earth removing device according to claim 3, wherein the fixed screen and the rotary screen hold foreign matter penetrating the eyes of the rotary screen. 12. A detecting means for detecting that the foreign matter is captured by the foreign matter capturing means is provided, and the detecting means detects a torque for rotating the rotating screen or the rotating screen. Rotation detecting means for detecting the rotation of the rotating screen, the fixed screen and the rotating screen retain the foreign matter penetrating the eyes of the fixed screen and the eyes of the rotating screen, thereby rotating the rotating screen. The earth removing device according to claim 11, which detects that the torque for the rotation is increased and the rotation of the rotating screen is decreased. 13. The soil discharging device according to claim 3, wherein a discharge port for taking out the foreign matter is provided in the vicinity of the foreign matter catching means. 14. The soil discharging device according to claim 3, further comprising a gate provided upstream of the foreign matter capturing means.