JPH0141837Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to an operating device for a closed shield excavator.

(Prior art) The present inventors originally wrote in Utility Application No. 59-31299,
The screw outer cylinder is connected to the intermediate part of the excavated soil discharge screw conveyor connected to the front partition wall in the shield body through an intermediate rotating part that rotates at a variable speed in the same or opposite direction to the rotational direction of the screw blades. The screw outer cylinder and the screw blades are rotated in the same direction at the same rotational speed so that the conveying force at the intermediate rotating part is 0, and the excavated soil is pushed in by the conveying capacity of the screw blades on the face side of the screw conveyor. The method is to prevent the excavated soil from blowing out by adjusting the degree of consolidation by changing the relative speed between the screw outer cylinder and the screw blade in the intermediate rotating section, Furthermore, by rotating the screw outer cylinder and the screw blades in the same direction in the intermediate rotating section, the circumferential speed of the excavated soil on the inner surface of the screw outer cylinder is increased, and the earth and sand are not sufficiently kneaded. We proposed an enclosed shield excavator that can improve the mixing condition even when the material is mixed.

(Problems to be solved by the invention) The closed shield excavator can be rationally controlled, and while effectively maintaining the safety of the face.
There is a need for an operating device for a closed shield excavator that can remove soil.

(Means for solving the problem) The present invention was proposed in response to such a request, and through repeated tests of the enclosed shield excavator, it was discovered that the number of rotations of the intermediate rotating section could be controlled. However, if the earth pressure inside the screw conveyor is equal to or higher than the earth pressure inside the chamber, no eruption will occur.

If the earth pressure inside the screw conveyor is increased too much, the installed torque of the drive source will be insufficient, and the screw blades will become more abrasive.

Even if the screw rotation speed increases or decreases due to changes in soil quality or excavation speed, the ratio of rotation speed of the intermediate rotating section/screw rotation speed may remain approximately the same.

It was revealed that.

The present invention was proposed based on the above knowledge, and the screw outer cylinder is installed in the middle part of the screw conveyor for excavated soil discharge connected to the front partition wall inside the shield body, and the screw outer cylinder is installed in the same or opposite rotation direction of the screw blades. In a closed type shield excavator equipped with an intermediate rotary section that rotates at variable speeds, a first earth pressure gauge is installed in the chamber in front of the front bulkhead, and a second earth pressure gauge is installed on the screw conveyor. A chamber earth pressure controller is connected to the first earth pressure gauge to transmit the information to the drive source of the screw conveyor based on the set earth pressure, and the second earth pressure gauge is connected to the chamber earth pressure controller which transmits the information to the drive source of the screw conveyor based on the set earth pressure. A screw conveyor earth pressure regulator is connected to the drive source, and a computing unit is connected to the drive source of the intermediate rotating section to compare and calculate a set value based on the detection signal of the screw conveyor rotation speed detector. The present invention relates to an operating device for an enclosed shield excavator characterized by the following.

(Function) In the present invention, as described above, a chamber earth pressure controller is connected to the first earth pressure gauge installed in the chamber in front of the front bulkhead, which transmits a signal based on the set pressure to the drive source of the screw conveyor. Therefore, if the pressure inside the chamber is higher than the set pressure of the controller, a signal is given to the screw conveyor's drive body to increase the rotation, and conversely, if the pressure is below the set pressure, it is sent to the drive source to decrease the rotation speed. A signal is given to keep the chamber internal pressure at a manageable soil pressure for stable excavation with the intermediate rotating section fixed, that is, in a normal screw conveyor condition.

However, if only soil pressure control in chambers is used, eruptions often occur in soils with high hydraulic conductivity and high water pressure.

Therefore, in the present invention, the earth pressure inside the screw conveyor is measured by a second earth pressure gauge inside the same conveyor, and when the earth pressure exceeds or falls below the set pressure, the earth pressure inside the screw conveyor connected to the screw conveyor is measured by the earth pressure gauge. Sending a signal to the drive source of the intermediate rotation part by the earth pressure regulator to reduce the rotation speed of the screw outer cylinder in the same part,
Alternatively, the rotation speed increases, and the intermediate rotating section is accelerated or decelerated.

Also, the screw conveyor rotation speed changes depending on the chamber internal pressure or the soil pressure in the face chamber, but if the ratio between the outer cylinder rotation speed of the intermediate rotating section and the screw conveyor rotation speed is kept constant, the screw conveyor Since it is clear from the above test results that the soil pressure in the screw conveyor is constant, a calculator connected to the calculator is used to compare and calculate the set value based on the screw conveyor rotation speed detection signal. By changing the rotational speed of the outer cylinder of the intermediate rotating section, the ratio of the rotational speeds of both screws is maintained constant even if the screw conveyor rotational speed changes, and subsequent fine adjustments are made.

(Example) The present invention will be described below with reference to the illustrated embodiments.

1 is the shield body, 2 is the shield jacket, 3
4 is a cutter drive motor, 4 is a cutter gear attached to the drive shaft of the motor, 5 is a cutter bearing having a large gear meshing with the same gear 4, 6 is a cutter, 7, 8
1 is a dirt seal for cutters, 9 is a bulkhead, 10 is a rotary joint, and 11 is a support arm for the rotary joint, which includes a valve 12 disposed on the bulkhead 9 and piping connected to the rotary joint 10. , the mud can be pushed into the gaps between the soil particles in front of the cutter 6. 13 and 1
Reference numeral 4 denotes a valve and a pipe for supplying mud to the chamber divided by the partition wall 9. Reference numeral 15 denotes a screw shaft of the screw conveyor that passes through the partition wall 9 and communicates with the chamber; 16 is a screw blade; 17 is the screw outer cylinder connected to the partition wall 9; and 18 is a rear screw outer cylinder, which includes both front and rear outer cylinders. 17 and 18 are respectively connected to a casing 19 of the intermediate rotating section.

Reference numeral 20 denotes a screw outer cylinder of the intermediate rotating section, which is provided with a large gear 23 that meshes with a small gear 22 attached to the drive shaft of a rotary drive motor 21 mounted on the casing 19, and drives the rotary drive motor 21. In some cases, the screw outer cylinder 20 rotates in the same or opposite direction to the rotational direction of the screw blades 16.
Moreover, it is configured to rotate at a variable speed.

In the figure, 24 is a bearing, 25 is an earth and sand seal, 26 is a bearing portion of the screw shaft, 27 is a screw shaft drive motor, and 28 is a gate.

Reference numeral 29 denotes a first earth pressure gauge for measuring the earth pressure of the chamber, and one or more of them are attached to the shield main body 1 facing into the chamber. A second earth pressure gauge 30 measures the earth pressure inside the screw conveyor, and one or more earth pressure gauges are attached to the screw outer cylinder 17.

Next, the principle diagram of soil pressure management shown in Fig. 2 will be explained.

When excavation is progressing smoothly with the screw outer cylinder 20 fixed, that is, in a normal screw conveyor condition, the soil pressure at position a indicates the soil pressure of the chamber, and X is the appropriate soil pressure for stable excavation. The earth pressure at position b indicates the underground pressure, or a soil pressure very close to it, since the earth is discharged into the mine at position b (the position of the gate discharge port), but when excavating under high water pressure, When excavating in soil with a high permeability coefficient, such as a water-retaining gravel layer, the water-tightness of the screw conveyor is always insufficient, even if sufficient mud is added and mixed, and the excavated soil tends to erupt. As shown by line d in Figure 2, the face management earth pressure decreases and the face becomes unstable.

Furthermore, if the rotational speed of the screw blades 16 and the rotational speed of the screw outer cylinder 20 in the intermediate rotating section are set to be approximately the same, soil will not be removed due to the co-rotation effect, but on the contrary, the soil pressure distribution within the screw conveyor will be on the f-line. As shown in the figure, the earth pressure exceeds the control level, and the screw torque and cutting torque become large, making it impossible to rotate, consolidating earth and sand in the chamber more than necessary, and causing wear and tear on each part of the shield machine. It becomes easier.

There are various cases in which it is necessary to control the rotation speed of the screw outer cylinder 20 while managing it with the earth pressure gauge 30 inside the screw conveyor so that the soil pressure inside the screw conveyor does not erupt and the controlled earth pressure X does not change. It was found in the test.

Now, if the appropriate earth pressure in the screw conveyor is line e, and the control earth pressure of one or more of the second earth pressure gauges 30 is Y ₁ and Y ₂ , then the screw outer cylinder should be adjusted so as to approach it. Just adjust the rotation speed.

The test results also revealed that if the ratio of screw outer cylinder rotational speed/screw conveyor rotational speed is equal, the earth pressure inside the screw conveyor remains almost the same.

An example of a control circuit using the test results is shown in FIG. 3. Reference numeral 29 is the first earth pressure gauge for measuring the earth pressure in the chamber or face, and 30 is the first earth pressure gauge for measuring the earth pressure in the screw conveyor. Although one or more earth pressure gauges are installed in each of the two earth pressure gauges, here, for the sake of simplicity, we will use one each.

27 is a screw conveyor rotation drive source, and 21 is a screw outer cylinder rotation drive source, both of which can be accelerated or changed in speed by a signal.

35 is a screw conveyor rotation detector;
Reference numeral 36 denotes screw outer cylinder rotation speed detectors, each of which is installed at a position on the machine side where it can be detected.

32 is a screw conveyor rotation speed indicator connected to the detector 35, and 33 is a screw outer cylinder rotation speed indicator connected to the detector 36.

Reference numeral 31 indicates an indicator for soil pressure at the face or chamber, which is connected to the earth pressure gauge 29, and 34 indicates an indicator for an earth pressure gauge in the screw conveyor, which is connected to the earth pressure gauge 30.

Therefore, if the controlled earth pressure On the other hand, if the pressure is below the set pressure, a signal is given to the screw drive source to reduce the rotation speed, and the drive source reduces its rotation.

Since the rotational speed of the screw at those times is detected by the detector 35 and indicated to the indicator 32, the operator can monitor and manage the changes, or input them to the recorder and record them. . The earth pressure indicator 34 in the screw conveyor is instructed by the output signal of the earth pressure gauge 30, and each of the indicators 3
Similar to 1 and 32, it is also possible to input only the instruction or to input it into the recorder.

Reference numeral 40 is a controller that adjusts the controlled earth pressure inside the screw conveyor, and if the controlled earth pressure Y is set, when the earth pressure inside the screw conveyor exceeds Y, the screw outer cylinder drive source 21 will be activated. The signal acts to lower the rotation, and the drive source 21 lowers. Conversely, if it is less than Y, a signal is output to increase the rotation, and the rotation of the drive source 21 increases. This rotation is detected by the screw outer cylinder rotation detector 36 and the indicator 3
Indicated by 3.

41, 42 and 43 are switches, and 43 is
If it is set to ON and switches 41 and 42 are turned off, the rotational speed of the screw and the rotational speed of the screw outer cylinder will change depending on changes in the chamber earth pressure and the screw earth pressure, allowing stable excavation. In addition, the earth pressure in the chamber tends to change due to changes in excavation speed and other factors, and as a result, the rotation speed of the screw conveyor changes constantly as mentioned above, but the ratio of the rotation speed of the screw conveyor to the rotation speed of the screw outer cylinder is very large. Tests have shown that if the ratio is kept constant as mentioned above, it is possible to keep the soil pressure in the screw conveyor almost constant if the soil quality is the same.

In other words, turn on switches 41 and 42 and turn off 43.
If the set rotation speed ratio Z is input in advance to the calculator 37 that adjusts the ratio between the screw conveyor rotation speed and the screw outer cylinder rotation speed, then when the screw conveyor rotation speed changes, the ratio will be adjusted accordingly. The data is input to the calculator 38 accordingly. The arithmetic unit 38 performs a composite operation on the input from the arithmetic unit 37 side and the input from the arithmetic unit 40 . For _{example ,} K ₁ X _{1 ±} K _{2 X 2} A method in which an instruction is given to the screw outer cylinder drive source 21, and subsequent fine adjustments are made through the controller 40 through the computing unit 38 so that the earth pressure is controlled by the controller 40, and then instructions are given again to the drive source 21. It is.

In this embodiment, a screw conveyor with a shaft is used, but the present invention can also be applied to a ribbon screw conveyor.

(Effects of the invention) As described above, in the present invention, based on the set pressure of the first earth pressure gauge attached to the chamber in front of the front bulkhead of the shield excavator, the pressure is connected to the first earth pressure gauge via the chamber earth pressure controller. The information is sent to the drive source of the screw conveyor to maintain the pressure inside the chamber at an appropriate level of soil pressure for stable excavation.If this chamber's soil pressure control alone is not sufficient, it will not be possible to eject water in soils with high water pressure and high permeability coefficients. Therefore, in this invention, in order to obtain an appropriate soil pressure inside the screw conveyor, the soil pressure inside the screw conveyor is measured by a second earth pressure gauge, and the same soil pressure is set. As the pressure increases or decreases, the rotation speed of the screw outer cylinder of the intermediate rotating section is decreased or increased through the screw conveyor soil pressure regulator, and the screw conveyor rotation speed is determined by the chamber internal pressure or the face chamber soil. Although it changes depending on the pressure,
The ratio of the rotation speed of the intermediate rotation member outer cylinder and the screw conveyor rotation speed is maintained constant by the arithmetic unit, and even if the screw conveyor rotation speed changes, the rotation speed of the intermediate rotation member outer cylinder is changed. As a result, even under high water pressure, the screw conveyor and cutter can be driven and rotated with an appropriate driving torque, while preventing jetting even under high water pressure. The present invention has many advantages, such as being able to control the rotation speed of the screw conveyor regardless of the change in rotation speed.

[Brief explanation of the drawing]

Fig. 1 is a vertical sectional side view of a sealed shield excavator equipped with an embodiment of the operating device according to the present invention, Fig. 2 is a diagram of the soil pressure management principle, and Fig. 3 is a control circuit diagram of the operating device. be. 9... Partition wall, 15... Screw shaft of screw conveyor, 20... Screw outer cylinder of intermediate rotating section, 29... First earth pressure gauge, 30... Second earth pressure gauge, 37, 38... Calculation 39...Chamber earth pressure regulator, 40...Screw conveyor earth pressure regulator.

Claims (1)

[Scope of utility model registration request] An intermediate rotating part is installed in the middle of the screw conveyor for excavated soil discharge connected to the front bulkhead inside the shield body, in which the screw outer cylinder rotates at a variable speed in the same or opposite direction to the rotational direction of the screw blades. In a sealed shield excavator, a first earth pressure gauge is attached to the chamber in front of the front bulkhead, a second earth pressure gauge is attached to the screw conveyor, and the earth pressure gauge is set to the first earth pressure gauge based on the set earth pressure. A chamber earth pressure regulator is connected to the drive source of the screw conveyor, and a screw conveyor earth pressure regulator is connected to the second earth pressure gauge, which transmits to the drive source of the intermediate rotating section based on the set earth pressure. An operating device for an enclosed shield excavator, characterized in that a computing unit is connected to the drive source of the intermediate rotating section to perform a comparison calculation with a set value based on a detection signal from a screw conveyor rotation speed detector.