JP2809380B2 - Tail clearance measuring device of shield excavator and attitude control device of shield 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 shield clearance excavator tail clearance measuring device and a shield excavator attitude control device, and is particularly useful for controlling the attitude of a shield excavator during tunnel excavation. .

[0002]

2. Description of the Related Art FIG. 11 is an explanatory view conceptually showing an entire shield excavator used for excavating a tunnel. As shown in the figure, a cutter 2 for excavation is provided on the front surface of a tubular shield machine main body 1, and a cutter 2 is provided inside the shield machine main body 1.
A screw conveyor 3 is provided to carry out the earth and sand excavated in the above section rearward.

[0003] The rear part of the shield machine main body 1 is a tail plate 1a facing the outer peripheral surface of the segment 4 assembled on the excavated portion. In the vicinity of the tail plate 1a inside the shield machine main body 1, a large number of shield jacks 5 distributed at equal intervals in the circumferential direction of the segment 4 are provided.
Are arranged so as to be opposed to the front end surface of the main body. Thus, by extending the piston rod 5a of the shield jack 5 and contacting the distal end thereof with the distal end surface of the segment 4 to receive the reaction force, the shield machine main body 1 moves forward (leftward in the figure).
It is configured to be able to move to.

The segment 4 is transported to a predetermined position by an erector device 6 disposed inside the tail plate 1a, and is assembled by being combined with the already assembled segment 4.

[0005] The construction of a tunnel using such a shield excavator is generally performed by repeating the operation of assembling the segments 4 along the inner wall of the tunnel behind the shield machine main body 1 after the shield excavator has excavated a predetermined distance. .

At the time of such work, when excavating by the shield excavator, it is determined whether or not the gap between the outer peripheral surface of the assembled segment 4 and the inner peripheral surface of the tail plate 1a is within a predetermined distance. There is a need to. This is because when the shield excavator digs along a straight path, it is determined whether the gap is within a predetermined dimension to determine whether the shield excavator is traveling straight.

[0007] Incidentally, the fact that the shield excavator does not fit within the predetermined size means that the shield excavator is not traveling straight.
Therefore, in such a case, the shield jack 5
It is necessary to correct the gap by correcting the posture of the shield machine body 1 by changing the amount of expansion and contraction of the piston rod 5a and changing the shield jack 5 to be selected. The modification of the attitude of the shield machine main body 1 is also necessary so as not to hinder the later assembly of the segment 4.

Conventionally, the measurement of the gap between the inner peripheral surface of the tail plate 1a and the outer peripheral surface of the segment 4 has often relied on manual labor of an operator. That is, the tail plate 1a
The measurement was performed by applying a scale between and segment 4.

[0009]

In the above-described manual measurement by the operator, not only the work is troublesome, but also accurate measurement is difficult.

[0010] Further, it is an obstacle to automation of a series of operations such as automatic excavation and automatic direction control of the shield excavator.

When measuring the tail clearance using a measuring instrument, an ultrasonic sensor, a laser sensor, or the like may be used. In this case, however, the sensor itself is too large to be installed in the tail clearance.
There is a problem that it is not suitable for measurement of a minute gap (50 mm or less), is weak to water, and there is a restriction on a use environment.

Further, a sensor using a proximity switch has been considered as a measurement sensor. In this case, since the output is only ON / OFF, the measurement range is narrow. There are problems such as that a plurality of different proximity switches must be installed, and it is difficult to utilize as data for automatic direction control because the output is not analog.

SUMMARY OF THE INVENTION In view of the above prior art, the present invention makes it possible to accurately and easily and automatically measure a tail clearance, which is a gap between a tail plate and a segment of a shield excavator, and to set a posture of the shield excavator at the time of excavation. It is an object of the present invention to provide a shield excavator tail clearance measuring device and a shield excavator attitude control device, which can automatically hold the shield excavator as predetermined.

[0014]

A first aspect of the present invention for achieving the above object is as follows.
The structure of the invention of the present invention is a cylindrical excavator having a cylindrical tail plate, which is a rear part of a shield machine main body, and which is distributed in a circumferential direction on the inner peripheral surface of a cylindrical tail plate, and is formed of a cylindrical segment assembled inside the tail plate. A plurality of magnetic sensors disposed so as to face the outer peripheral surface, and information processing means for processing an output signal of each magnetic sensor to detect a tail clearance which is a distance between the inner peripheral surface of the tail plate and the outer peripheral surface of the segment. And characterized in that:

According to a second aspect of the present invention, a shield machine is provided in which a front end surface of a cylindrically assembled segment abuts inside a cylindrical tail plate which is a rear portion of a shield machine main body, and this segment is used as a reaction force receiver. An attitude control device for a shield excavator having a plurality of shield jacks arranged in a circumferential direction inward of a tail plate so as to advance a main body, and is distributed in a circumferential direction on an inner circumferential surface of the tail plate.
And a plurality of magnetic sensors arranged so as to face the outer peripheral surface of the cylindrical segment assembled inside the tail plate, and the output signal of each magnetic sensor is processed to process the inner peripheral surface of the tail plate and the segment. Control means for detecting a tail clearance, which is a distance from the outer peripheral surface, and controlling each shield jack so that each distance is equal.

[0016]

According to the first aspect of the present invention, the distance to the outer peripheral surface of the segment, that is, the tail clearance is detected by processing the output signal of the magnetic sensor.

According to the second invention, the amount of expansion and contraction of the piston rod of the shield jack is adjusted based on the tail clearance detected by the first invention so that each tail clearance becomes the same, and the shield machine main body and the segment are adjusted. To maintain concentricity.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below in detail with reference to the drawings. The same parts as those in the related art are denoted by the same reference numerals, and redundant description will be omitted.

FIG. 1 is a vertical sectional view showing the portion A of FIG. 11 in an extracted and enlarged manner. As shown in the figure, a tail packing 7 is provided at the rear of the tail plate 1a. The tail packing 7 contacts the outer peripheral surface of the existing segment 4 to prevent earth and sand from entering the tail plate 1a, and is formed of a brush, rubber, or the like.

In the tail clearance measuring device according to the present embodiment, a concave portion 1b formed on the inner peripheral surface near the rear end of the tail plate 1a is opposed to the outer peripheral surface of the segment 4, and the distal end surface is formed on the inner peripheral surface. A magnetic sensor 8 is provided so as to slightly project from the steel segment 4.
An output signal of a level corresponding to the distance up to is output.

As shown in FIG. 2, which is a view taken along the line BB of FIG. 1, the magnetic sensor 8 has a conductor 9 for transmitting its output signal.
Is sent out to the outside along the groove 1c formed in the inner peripheral surface of the tail plate 1a so as to be continuous with the concave portion 1b, and the tail made of a magnetic material is surrounded by a mold material 10 made of a non-magnetic material. It is isolated from the plate 1a to eliminate its influence.

Further, in this embodiment, as shown in FIG. 3, the magnetic sensors 8 are arranged at a total of four locations on the inner peripheral surface of the tail plate 1a: a top portion, a ground portion, a left portion and a right portion. It is. These are denoted by reference numerals 8a, 8b, 8c and 8d in order.

In this embodiment, the four magnetic poles are
Since it has the air sensors 8a to 8d, as shown in FIG.
The center of the tail plate 1a and the segment 4 is the same,
That is, when concentric, each of the magnetic sensors 8a to 8d
Distance output l represented by the output signal _a, L_b, L_c, L_dIs
Value.

On the other hand, as shown in FIG. 5, when the center of the tail plate 1a and the segment 4 are deviated and the clearance of the ground portion becomes narrow, the distance outputs l _c and l _d of the left and right magnetic sensors 8c and 8d become Although equal, the distance output l _{a at the top} is large and the distance output I _{b at the} ground is small.

As described above, the output signals of the magnetic sensors 8a to 8d provided on the left and right sides of the tail plate 1a
The attitude control device shown as another embodiment controls the shield jack 5 by calculating the deviation between the center of the segment 4 and the center of the segment 4. That is, in this attitude control device, the output signals of the magnetic sensors 8a to 8d are supplied to the controller 11, as shown in FIG. Controller 1
In 1 processes the output signal of the magnetic sensor 8 a to 8 d, the center O ₂ of the center O ₁ and segment 4 tail plate 1a
And the direction thereof are detected, and the amount of expansion and contraction of the piston rod 5a of each shield jack 5 is selectively controlled via the shield jack hydraulic circuit 12 so that the centers O ₁ and O ₂ coincide.

FIGS. 7 and 8 are principle diagrams showing the principle of the preferred embodiment as the magnetic sensor 8. FIG. FIG. 7 shows a high-frequency transmission type in which a change in impedance of the detection coil 8e is detected and output when a detection object, that is, a steel segment 4 approaches. FIG. 8 shows a differential coil type in which a magnetic flux due to an eddy current generated in the detection object, that is, the detection object due to the approach of the steel segment 4 is detected and output by the difference between the detection coil 8f and the comparison coil 8g.

In any case, the detection output P increases as the detection object, that is, the steel segment 4 approaches, so that the distance l and the detection output P are in inverse proportion.

FIG. 9 shows the arrangement of a magnetic sensor according to another embodiment. In this embodiment, a plurality of magnetic sensors 8a to 8d arranged in the circumferential direction in the above-described embodiment and another set of magnetic sensors 8a to 8d at a position separated in the axial direction of the shield machine main body 1 are respectively provided. This is the one in which the corresponding magnetic sensor 13 is added.

That is, according to the present embodiment, two tail clearances disposed with a certain span in the axial direction can be detected, so that the central axis L of the tail plate 1a in the axial direction of the tail plate 1a can be detected based on both detected values. ₁ and can detect the tilt angle θ between the center axis L ₂ of the same direction segments 4, three-dimensional relative positional relationship between the tail plate 1a and segment 4 in conjunction with planar tail clearance data by the magnetic sensor 8a~8d Becomes clear. Therefore, by using this data, data processing is further facilitated, and a predetermined attitude control can be easily performed.

[0030]

As described above in detail with the embodiment, according to the present embodiment, the direct value of the gap dimension between the tail plate and the segment can be detected in real time, and the relative distance between the tail plate and the segment can be detected. The positional relationship becomes clear, and automation of the attitude control of the shield excavator can be easily realized.

Further, since the magnetic sensor can perform a predetermined measurement without any problem even when immersed in water, the initial description can be well exhibited even in a bad environment to which the shield excavator is applied.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing an embodiment of the present invention.

FIG. 2 is a view taken along line BB of FIG. 1;

FIG. 3 is an explanatory view conceptually showing a mounting position of a magnetic sensor in the embodiment.

FIG. 4 is an explanatory view conceptually showing an aspect at the time of measuring tail clearance.

FIG. 5 is an explanatory view conceptually showing another mode at the time of measuring the tail clearance.

FIG. 6 is a block diagram showing a posture control device according to the embodiment of the present invention.

FIG. 7 is a principle view showing a magnetic sensor used in an embodiment of the present invention.

FIG. 8 is a principle view showing another magnetic sensor used in the embodiment of the present invention.

FIG. 9 is an explanatory view showing another arrangement mode of the magnetic sensor.

FIG. 10 is an explanatory diagram showing a mode of a shift of a center axis between a tail plate and a segment in the case of FIG. 9;

FIG. 11 is an explanatory view conceptually showing the entire shield excavator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shield machine main body 1a Tail plate 4 Segment 5 Shield jack 5a Piston rod 8, 8a, 8b, 8c, 8d, 13 Magnetic sensor 11 Controller

Claims (2)

(57) [Claims] 1. An outer periphery of a cylindrical segment that is distributed circumferentially on an inner peripheral surface of a cylindrical tail plate that is a rear portion of a shield machine body of a shield excavator and that is assembled inside the tail plate. A plurality of magnetic sensors disposed so as to face the surface, and information processing means for processing an output signal of each magnetic sensor to detect a tail clearance which is a distance between an inner peripheral surface of the tail plate and an outer peripheral surface of the segment. A tail clearance measuring device for a shield excavator, comprising: 2. A tail which abuts a front end face of a cylindrically assembled segment inside a cylindrical tail plate which is a rear portion of the shield machine main body, and advances the shield machine main body by using the segment as a reaction force receiver. An attitude control device for a shield excavator having a plurality of shield jacks arranged in a circumferential direction inside a plate, wherein the shield excavator is distributed in a circumferential direction on an inner circumferential surface of a tail plate, and is disposed inside the tail plate. A plurality of magnetic sensors disposed so as to face the outer peripheral surface of the cylindrical segment assembled in the above, and processing the output signal of each magnetic sensor to determine the distance between the inner peripheral surface of the tail plate and the outer peripheral surface of the segment. Control means for detecting each tail clearance and controlling each shield jack so that each distance is equal to each other. The control device.