JP3285530B2 - Method for guiding tunnel excavation path in propulsion method and apparatus therefor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for guiding a tunnel excavation path in a propulsion method, and particularly to a technique for efficiently guiding an excavation path in both straight excavation and curved excavation. About.

[0002]

2. Description of the Related Art A tunnel propulsion method has many advantages such as not hindering traffic on the ground and reducing the diffusion of noise to the surroundings. For this reason, the propulsion method is used in excavation of various tunnels, such as tunnels for burying energy transmission paths such as power cables and information transmission paths such as telephone lines and optical fiber cables.

However, in the propulsion method, since the position of the tunnel excavation site and the direction of the excavation at that time cannot be directly confirmed in relation to the target point on the ground surface, a special technique for guiding the tunnel excavation path is required. Needed. As such a guidance method in the propulsion method, the following is conventionally known.

First, the first prior art is based on human power, and monitors the direction of the face by observing a target placed near the face from behind the tunnel by surveying.

In the second prior art, a laser beam is irradiated from the back of a tunnel to a target placed near a face, and the direction of the face is monitored by a laser transit behind the tunnel.

[0006]

However, in the first prior art, there is a problem that surveying work is difficult even in straight excavation because the tunnel yard of the propulsion method is narrow, and it takes a lot of work time.

[0007] In the recently developed curved excavation,
Due to the peculiarity of the propulsion method in which the lining pipe at the bent portion also moves as the construction progresses, a reference point cannot be set for each bent portion. For this reason, every time the necessity of surveying arises, the survey must be performed again from the wellhead, and the time and labor required for the survey are further increased.

On the other hand, the second prior art is effective in straight excavation, but is difficult to use in curved excavation due to the straightness of laser light. In this regard, in curved excavation, it is conceivable to install a reflecting mirror or a laser light transmitting / receiving device for each bent portion. However, as described above, in the propulsion method, since the lining pipe of the bent portion also moves with the progress of the construction, the reflecting mirror and the laser light transmitting / receiving device must be re-installed each time with the progress of the construction. . For this reason, even if such an improvement is made, the loss of time and labor will be great.

[0009]

SUMMARY OF THE INVENTION The present invention is intended to overcome the above-mentioned problems in the prior art.
An object of the present invention is to provide a technique that can be applied to both straight excavation and curved excavation and that can efficiently guide an excavation path.

[0010]

In order to achieve the above object, the present invention uses electromagnetic waves in a radio wave band.

Unlike electromagnetic waves in the optical wavelength band, such as laser light, electromagnetic waves in the radio wave band can propagate through the ground. Therefore, electromagnetic waves are radiated into the ground and received near the face, and the receiving direction and The subsequent excavation guidance of the tunnel is performed by determining the reception intensity.

As is well known, the attenuation of electromagnetic waves is relatively greater in the ground than in the air. However, since the distance used for guiding the excavation of the tunnel is not long enough to be used for communication and the like, the electromagnetic wave in the radio wave wavelength band is used, and the distance that does not substantially attenuate the electromagnetic wave ( For example, it can sufficiently withstand excavation guidance from a position distant from tens to hundreds of meters.

A technique for magnetically detecting underground metal (for example, an existing water pipe) or the like to guide the excavation is conceivable, but the present invention is more active than such a passive method. Since the electromagnetic wave is transmitted and detected, the magnetic field intensity at the detection point is large and the detection accuracy is high.

In the following, the direction in which the excavation should be further advanced from the face at that time, that is, the direction appropriate as the excavation guiding direction will be referred to as the “proper guiding direction”.

[0015]

According to the present invention, the tunnel excavation path is guided at a reference position in front of the tunnel excavation direction.
Transmit coil arranged with the direction to be set as the coil axis direction
Transmits an electromagnetic field in the radio waveband from the
A wave is received near the face of the tunnel excavation road to obtain a received signal.
Therefore, the phase detection of the received signal is performed to isolate the received signal.
Calculate a pair value and a phase polarity, and calculate the absolute value and the phase polarity.
Based on both identifying the spatial relationship between the reference position and the tunneling path between, characterized by guiding the tunnel excavation path based on the spatial relationship.

According to a second aspect of the present invention, in the method of the first aspect, an electromagnetic wave having directivity is used as the electromagnetic wave.

According to a third aspect of the present invention, in the method of the second aspect, the reference position is set to an underground position.

[0018] In the invention of claim 4 is the method of claim 3, the direction should induce the tunneling path placing the transmitter coil to the ground position as the coil axis direction, and disposed near the working face receiving Receiving the electromagnetic wave with a coil minimizes the reception intensity of the receiving coil
With respect to the direction toward the receiving coil axis direction to the ground position
It is characterized by a right angle .

According to a fifth aspect of the present invention, in the method of the second aspect, the reference position is set to a ground surface position.

[0020]

[0021]

According to a sixth aspect of the present invention, there is provided an apparatus for guiding a tunnel excavation path in a propulsion method, wherein (a)
It can be installed at the reference position in front of the tunnel excavation direction,
Transmitting means having a transmission coil for transmitting an electromagnetic field in a radio wave wavelength band with the direction in which the tunnel excavation path should be guided as a coil axis direction; and (b) receiving the electromagnetic wave near a face of the tunnel excavation path, Receiving means for detecting an absolute value and a phase polarity of a received signal, and (c) display means for displaying an amount having a magnitude corresponding to the absolute value and having a sign according to the phase polarity. It is characterized by.

According to a seventh aspect of the present invention, in the apparatus of the sixth aspect , the transmitting means is disposed at a first reference position in the ground to guide the tunnel excavation path. Y
A first transmitting coil (21) whose coil axis is aligned with
(a-2) It is located at the second reference position on the ground and is in the vertical direction Z
And a second transmission coil (31) whose coil axis is matched. Correspondingly, the receiving means may be configured as (b-
1) A horizontal coil (11Y) and (b-2) a V-shaped coil (11V) arranged in a vertical plane (XZ) perpendicular to the horizontal coil (11Y) and having a symmetric axis in the vertical direction Z. Have. Further, the display means (c-1) a first meter (260) for displaying the reception signal of the horizontal coil (11Y) with a sign according to the phase polarity thereof,
(c-2) a second meter (360Z) for displaying the vertical component of the received signal of the V-shaped coil (11V) with a sign according to the phase polarity thereof, and (c-3) the V-shaped coil A third meter (360) that displays the horizontal component of the received signal of the coil (11V) with a sign according to the phase polarity of the signal.
X).

[0024]

DESCRIPTION OF THE PREFERRED EMBODIMENTS * <Overall configuration and basic principle>
FIG. 1 is a diagram showing an example of a situation to which an embodiment of the present invention is applied, and schematically shows a situation where a tunnel 1 is being excavated in the ground by a propulsion method. FIG. 2 is a schematic plan view showing only a portion related to a transmission unit and a reception unit of the electromagnetic wave when seeing FIG. 1 from above. In FIGS. 1 and 2, for the sake of convenience of description, a rectangular coordinate system is defined in which a plane (horizontal plane) parallel to the ground surface H is defined as the XY directions and a vertical direction is defined as the Z direction. Here, X
As the direction, the direction in which the excavation guidance of the tunnel 1 is to be performed at that time is taken, but this is for convenience.

The excavator 2 is a well-known propulsion method, and excavates the tunnel 3 while excavating the face 3. As described in detail below, by transmitting electromagnetic waves in the radio waveband from the transmitting units 20A and 30A disposed in the ground and underground in the excavation direction, respectively, and receiving them by the receiving unit 10A. The direction of the subsequent excavation by the excavator 2 can be guided. In the illustrated example, the receiving unit 10
A is disposed on a support 2B projecting backward from the excavator 2.

Since the excavator 2 includes many metal parts,
The electromagnetic wave cannot pass through the excavator 2 as it is.
However, unlike the light wave, the electromagnetic wave in the propagation area can go around to the rear of the excavator 2, so that the excavator 2
Is not an essential obstacle to the reception of electromagnetic waves.

Although FIG. 1 and FIG. 2 show the straight tunnel 1, the method of this embodiment utilizes electromagnetic waves propagating in the ground, so that the curved tunnel 1a shown by a broken line in FIG. However, this guidance method is applicable. This is because it is not necessary to carry out surveying in the section from the entrance to the face 3 in order to carry out the method of the present invention.

Hereinafter, the configuration and operation of each section will be sequentially described.

* <Outline of underground transmission system> A boring pit 5 is dug in front of the tunnel 1 in the direction of excavation, and a portable underground transmission unit 20A is disposed at an underground reference position RD therein. Have been. In the underground transmission unit 20A, as shown in FIG.
And a transmission circuit section 22 for supplying a transmission power of about 1 kHz to a case, which is housed in a case made of a material (for example, resin) having electromagnetic wave permeability. Coil axis A ₂₁ is the guidance direction of the tunnel 1 in FIGS. 1 and 2 of the transmitter coil 21, and more specifically there is a direction (X direction) toward the vicinity of the working face 3. A portable transmission power supply unit 20B is placed on the ground surface in FIG. 1, and supplies power to the transmission circuit unit 22 in FIG. The electromagnetic wave radiated from the transmission coil 21 is a directional electromagnetic wave having symmetry such that the coil axis A ₂₁ of the transmission coil ₂₁ is a symmetric axis.

* <Overview of Ground Transmission System> On the other hand, in FIGS. 1 and 2, the ground reference position P corresponding to the ground surface in the excavation direction of the tunnel 1 and above the target excavation position of the tunnel 1 is portable. Is disposed. In the ground surface transmitting unit 30A, as shown in FIG. 4, a transmitting coil 31 and approximately 1 kHz
And a transmission circuit section 32 that supplies the transmission power of the transmission power are housed in a case formed of a material (for example, resin) having electromagnetic wave transparency. Unlike underground transmission unit 20A of FIG. 3, the coil axis A ₃₁ of the transmitting coil 31 of FIG. 4 is a vertical direction Z
It has become. As shown in FIG.
, A portable transmission power supply 30B is also provided, and supplies power to the transmission circuit 32 of FIG. 4 by a cable.

The electromagnetic wave radiated from the transmission coil 31 is also a directional electromagnetic wave having symmetry such that the coil axis A ₃₁ of the transmission coil ₃₁ is a symmetric axis.

* <Outline of the receiving system> The receiving unit 10A of FIG.
5 is shown in a perspective view in FIG.
In FIG. 5, three receiving coils 11Y and 11Y are contained in a case 13 made of a material (for example, resin) having electromagnetic wave transmission.
1a and 11b are arranged. Front 13 of case 13
Speaking of the azimuth relationship in a state where F is directed to the current appropriate guidance direction of the tunnel 1, the arrangement relationship is as follows.

The first receiving coil 11Y has a coil axis A _Y in a direction substantially perpendicular to the current excavation direction of the tunnel 1 in the horizontal plane, that is, the surface of the face 3 in the coordinate system of FIG. Are arranged so as to face a direction Y substantially parallel to. The first receiving coil 11Y is used for receiving an electromagnetic wave from the underground transmission unit 20A in FIG. 1 and guiding the face 3 in the horizontal direction (left and right direction), as described later.

The second receiving coil 11a and the third receiving coil 11b are connected to each other and
It is used as 1V. Then, each of the coil axis A _a of the second receiver coil 11a and the third receiving coil 11b, A _b is a V-type symmetrical with respect to substantially a perpendicular vertical plane and the vertical axis Z in the working face 3 These receiving coils 11a and 11b are arranged so as to be as follows. The vector detection coil 11V composed of the pair of coils 11a and 11b mainly performs excavation guidance in the vertical direction (depth direction) and receives the electromagnetic wave from the ground surface transmission unit 30A in FIG. It is also used to guide excavation to just below.

The winding directions of the coils of these two receiving coils 11a and 11b may be the same or opposite.
In the apparatus of this embodiment, the winding directions of the coils 11a and 11b are the same (for example, clockwise). The reception voltage of the reception coils 11a and 11b is detected using the wiring G taken out from the interconnection point as a reference potential.

The receiving section 10A also has a built-in receiving circuit section 12, and wiring extending from each of the coils 11X, 11a, 11b is connected to the receiving circuit section 12. The receiving circuit unit 12 is connected to the monitor unit 10M in FIG. 1 via a cable 10C. The monitor 10M monitors and displays the reception status of the receiver 10A. In addition, a portable excavator operation unit 2A (FIG. 1) for remotely operating the excavator 2 to maintain or change the excavation direction is installed on the ground surface, and excavates via a cable 2B shown by a broken line. Connected to the device 2.

A support 2B extending rearward from the excavator 2 of FIG. 1 is provided with a receiver drive mechanism 2D, whereby the direction of the receiver 10A can be changed by remote control. Such changes in orientation include both turning in the horizontal plane and vertical elevation. The cable 2B can transmit not only the remote control of the excavator 2 itself but also a remote control signal of the receiving unit rotating mechanism 2D. The excavator operation unit 2A may be provided with an operation unit for remote-controlling the receiving unit rotation mechanism 2D.

The power supply to the monitor unit 10M and the excavator operation unit 2A can be performed, for example, by driving a 12V battery.

* <Principle of Guiding Direction of Excavation Direction> Before describing the detailed circuit configuration of each part described above, the principle of guiding the excavating direction by this system will be described first. FIG. 6 is a schematic view of the positional relationship between the transmitting coil 21 disposed underground and the receiving coil 11Y in the receiving unit 10 as viewed from above.
However, the broken line indicates the symmetric distribution of the magnetic flux lines in the transmission electromagnetic wave. In FIG. 6, there are receiver coils 11Y on the extension line of the axis A21 of the transmitter coil 21, and there the axis A _Y of the receiving coil 11Y is perpendicular to the axial direction A ₂₁ of the transmitting coil 21 (i.e. just in the Y direction, In the state F1 as shown in FIG.
With the center of Y as the axis of symmetry, magnetic fluxes in the opposite direction and of the same magnitude penetrate through the half on one end and the half on the other end of the receiving coil 11Y. Therefore, the reception intensity of the reception coil 11Y becomes minimum (ideally zero). Although the magnetic flux is depicted in FIG. 6 as a static magnetic field, the above situation does not change even if the transmission electromagnetic wave is an alternating current wave and the magnetic flux distribution changes dynamically. This is because the above situation is based on spatial symmetry.

On the other hand, the axis A _{Y of the} receiving coil 11Y
There or tilted from the Y direction as in the state F2, the axis A _Y of the receiving coil 11Y is or are off-axis A _{2 1} transmission coil 21 as a state F3, symmetry of the magnetic flux passing through the inside of the receiving coils 11Y And the voltage appears at both ends of the receiving coil 11Y. This reception intensity (more precisely, the amplitude of the received electromagnetic wave) increases in accordance with the magnitude of the deviation from the symmetric state F1, and the phase of the reception voltage changes the polarity of the direction deviation of the receiving coil 11Y from the symmetric state F1. Reflects.

Accordingly, the direction relationship between the transmission coil 21 and the reception coil 11Y can be known from the reception voltage of the reception coil 11Y. The receiving coil 11Y is connected to the receiving unit 1
0A (FIGS. 1 and 5), the receiving unit 10A near the face 3 of the tunnel 1 is located at that point in time with the underground transmitting unit 20A (therefore, the direction toward the underground reference position RD) and the horizontal plane. (Right and left directions when viewed from the face 3).

That is, in the vicinity of the face 3, the receiving unit 1
If a direction in which the reception intensity of the first receiving coil 11Y of 0A is minimized (ideally, zero) is found, the direction is a proper guiding direction toward the underground reference position RD, and excavation is performed in that direction. If the tunnel 2 is excavated, the tunnel 1 can be excavated along a predetermined line.

Whether the face 3 is shifted rightward or leftward from the target direction at that time can be known from the phase of the received voltage of the receiving coil 11Y.

[0044] In this case, the installation depth and direction of the transmitting portion 20A in the boring pits 5 in FIG. 2 (thus, the direction of the axis A ₂₁ of the transmitting coil 21, which is built therein)
Can be determined from the excavation plan of the tunnel 1. In the face 3, excavation may always be performed toward the underground reference position RD.

Further, in some cases the direction of the receiving coil 11Y is close reception intensity of the receiver coil 11Y is zero such as when there is significantly deviated state F4 from the direction of the axis A ₂₁ of the transmitting coil 21 in FIG. 6 obtain. However,
Since the guidance of the excavation direction is performed sequentially along the appropriate guidance direction, such abnormal sparseness rarely occurs, and the detection is usually performed in the state F1 or in the vicinity thereof. Has no substantial effect.

By the way, it is also possible to arrange a receiving coil in which the direction of the coil axis is the X direction, and set the direction in which the magnetic field detected by the receiving coil becomes maximum as the excavation guiding direction. However, if the direction of the minimum magnetic field is detected as in this embodiment, there are other advantages as described later. Therefore, in this embodiment, the direction guidance is mainly configured to detect the direction of the minimum magnetic field, and the maximum magnetic field is detected. Guidance by direction detection is used as an auxiliary.

On the other hand, if another receiving coil having the coil axis in the Z direction is provided for the same reason as the above-described principle of the receiving coil 11Y, the reception voltage of the receiving coil is detected, and the Receiver 1 near face 3
It is possible to know whether or not the direction of 0A is deviated in the vertical plane (vertical direction) from the appropriate guidance direction toward the underground transmitting unit 20A (the direction toward the underground reference position RD) at that time. That is, the first receiving coil 11Y is provided mainly for detecting the digging direction in the horizontal plane, while the other receiving coil is used for detecting the digging direction in the vertical plane.

For this reason, another receiving coil having the coil axis in the Z-axis direction may be provided. In this embodiment, such direction guidance in the depth direction is performed by the vector reception shown in FIG. This is performed using the coil 11V.

The vector receiving coil 11V has both functions of an X-direction coil and a Z-direction coil as described later. Here, the purpose of use of each receiving coil including the above-mentioned receiving coil 11Y is described in the following "Relationship". It is organized as "Table 1" and will be referred to later as appropriate. Here, “Y coil” = receiving coil 11Y “X coil” = X component of vector receiving coil 11V “Z coil” = Z component of vector receiving coil 11V.

The relation table 1 has already been described.

[Relation Table 1] ● At the time of direction detection X coil: maximum detection (left / right vertical guidance assistance) Y coil: minimum detection (left / right guidance) Z coil: minimum detection (vertical guidance) ● at target position detection X Coil: minimum detection (judgment of front / rear misalignment) Y coil: minimum detection (judgment of left / right misalignment) Z coil: maximum detection (assistance of judgment of front / rear misalignment) The operation of the vector receiving coil 11V is as follows. First, among the functions of the vector receiving coil 11V, directional guidance in a vertical plane (up and down or depth direction) will be described. It is assumed that the vector difference between the reception voltages of the second coil 11a and the third coil 11b in the vector reception coil 11V is determined. here,
As shown in FIG. 5, since the ground point G is taken out from the middle between both coils 11a and 11b, the signs of the received voltages of the two coils 11a and 11b are reversed. On the other hand, since both coils 11a and 11b constituting the vector receiving coil 11V are arranged close to each other, an external absolute coordinate system (XYZ
When viewed in a coordinate system, the direction and magnitude of the electromagnetic field in them are common. Therefore, these two coils 11
When the vector difference between the received voltages a and 11b is obtained, the Z components of the respective coils are canceled.

On the other hand, in the X direction, the coil 1
Since 1a and 11b are equivalent to coils in opposite directions, a vector difference between the reception voltages of these coils 11a and 11b is calculated as follows.
This corresponds to the reception voltage when the coupling of b is regarded as one coil extending in the X-axis direction. If it is referred to as “X coil” in accordance with the term in the above “Relation Table 1”, when the vector receiving coil 11V is in the appropriate guiding direction,
The X coil becomes coaxial with the coil axis A ₂₁ of the ground transmitter coil 21, receives voltage is maximized. Then, the received voltage decreases even if it is shifted left, right, up, or down. Therefore, in direction guidance, this X coil can be used for left, right, up and down guidance. However, since the detection of the minimum voltage is superior to the detection of the maximum voltage as described later, the direction guidance by the X coil is used in an auxiliary manner (see the row of "Relation Table 1"). .

Next, the vector sum of the reception voltages of the second coil 11a and the third coil 11b constituting the vector reception coil 11V will be considered.

In consideration of such a vector sum, each Z component is canceled out, and the two coils 11a, 11a,
11b can be regarded as one coil extending in the Z-axis direction. If this is called a "Z coil", when the vector receiving coil 11V is in the appropriate guiding direction,
According to the same principle as that of the Y coil (receiving coil 11Y), this Z
The receiving voltage of the coil is minimized. Then, the absolute value of the reception voltage increases regardless of whether it is shifted upward or downward. Therefore, in direction guidance, this Z coil is used for guidance in the vertical direction (vertical direction). (See row in "Relation Table 1").

The receiving coil 11Y and the vector receiving coil 11V can also be used to detect the excavation target point as to how far the excavation should be advanced or where the excavation direction should be changed.

Of these, the target point detection by the vector receiving coil 11V is based on the following principle. That is, since the magnetic flux from the transmitter coil 31 as shown in FIG. 7 has a rotational symmetry about the axis A _31, vector receiver coil 11V
In the state P1 in which the center axis A _ab of symmetry of the axis coincides with the axis A ₃₁ of the transmission coil 31, the second and third reception coils 11a and 11b
Are equal. Accordingly, in this case, the difference between these voltages (virtual X coil reception voltage) is minimized (ideally, zero).

On the other hand, in a state P2 in which the axis A _ab of the vector reception coil 11V is displaced from immediately below the axis A ₃₁ of the transmission coil 31, the reception voltages of the second and third reception coils 11a and 11b are different. . Then, the difference increases with distance from directly below the axis A _31. Therefore, the second and third
By monitoring the difference between the receiving voltages of the receiving coils 11a and 11b and guiding the excavation so as to minimize the difference, the excavation can be performed directly below the ground reference position RP corresponding to the target point of excavation (see "Relation Table 1"). "of). When it deviates from this target point back and forth, the received voltage increases in the positive or negative direction.

The same applies to the receiving coil 11Y (see "Relationship Table 1"), but the phase is inverted in the left-right direction depending on the direction of deviation.

On the other hand, the sum of the reception voltages of the two coils 11a and 11b of the vector reception coil 11V (the reception voltage of the virtual Z coil) becomes the maximum immediately below the ground reference position RP, and then the front, rear, left and right In any case, the absolute value decreases. This can be used to assist the target point guidance (of "Relation Table 1").

* <Circuit Configuration of Transmitter> FIG. 8 is a diagram showing a circuit configuration of the underground transmitter 20A and the ground surface transmitter 30A. The underground transmission unit 20A and the ground surface transmission unit 30A basically differ only in the axial direction of the transmission coil, and the other configurations are substantially the same.

The internal circuits of the transmitting units 20A and 30A are roughly divided into a precision frequency transmitting unit 110 and a transmitting coil unit 120. In the precision frequency transmission unit 110, the crystal oscillator 111 generates a 5 MHz megahertz wave,
In the / 5000 frequency dividing circuit 112, the frequency is reduced to a high frequency of 1 kHz. And a rectangular wave buffer 1
13 is a rectangular high frequency. This rectangular high frequency is transmitted to the tuning capacitor C in the transmitting coil unit 120 and the transmitting coil 2.
1 (or 31), the tuning component of 1 kHz is taken out, and the transmission coil 21 (3
From 1), an electromagnetic wave of 1 kHz is radiated.

Here, the transmission frequency is 1 kHz.
Is selected because the natural current (noise) is relatively small around 1 kHz. Also, as will be described later, the receiving unit performs phase detection, but includes an operation time for determining the direction of excavation guidance according to the reception result,
The frequency accuracy is maintained for about 10 seconds.

Since it is preferable to transmit as high an electromagnetic wave as possible from the transmission coil 21 (31),
In the LC series resonance circuit in the oscillation coil section 120, the series resistance component is reduced to increase the Q value.

The elements 111 to 113 in FIG. 8 are parts accommodated in the transmission circuit section 22 in FIG. 3 and the transmission circuit section 23 in FIG.

The electromagnetic wave used is 1 k as described above.
Hz is most preferable, but other than that, a preferable range is, for example, a range of 0.5 kHz to 5 kHz, and furthermore, an electromagnetic wave in a range of about 0.1 kHz to 100 kHz can be adopted. If short-range guidance is sufficient, a higher frequency range may be selected in the radio wave wavelength band.

* <Circuit Configuration of Receiving Unit> * <Y Lead> FIG. 9 is a circuit diagram showing a part of the receiving unit 10A for detecting and displaying a signal received by the first receiving coil 11Y. . In the receiving coil section 210 in the receiving section, the voltage between both ends of the receiving coil 11Y is buffered and amplified by the input buffer circuit 211.

The received signal thus amplified passes through a narrow-wave tuning amplifier (band-pass filter) 220 to selectively transmit a component near 1 kHz in the received signal. As a result, the noise component is cut off, and the signal becomes suitable for detecting the minimum reception intensity.

The received signal substantially having only the frequency component near 1 kHz in this way is supplied to the next-stage two-phase detector 2.
30 is input. At the input stage of the two-phase detector 230, the received signal Vin is branched into two streams. The first unit detection circuit 231a is a timing circuit 232a that opens and closes the switch 133a with the reference signal v having the same frequency f as the transmission frequency (about 1 kHz in this embodiment).
It has. Also, the second unit detection circuit 231b
A second timing circuit 232b that opens and closes the switch 133b with a signal jv having the same frequency f and a phase shifted by 90 degrees from the first timing circuit 232a is provided. In the figure, the symbol “j” is an imaginary unit, and “jv”
Indicates that the signal has a phase component shifted by 90 degrees from “v”.

Of these, first, the first unit detection circuit 2
The operation of 31a will be described with reference to FIG. 10 (a) is an approximate representation of the waveform of the received signal Vin, and FIG. 10 (b) is a timing circuit 2
Opening / closing (ON / OFF) of switch 231a by 32a
Is shown.

First, when the phase of the received signal Vin and the timing signal TS are aligned as illustrated in FIG. 10, only the positive polarity portion of the received signal Vin is cut out, and FIG. ). Ninth
, A reception intensity signal V ₀ indicating the intensity of the reception signal Vin is obtained. However, the reception intensity signal V ₀ is a signal with a positive or negative sign, and if the reception signal Vin is the one obtained by inverting the waveform of FIG. 10A, the sign of the reception intensity signal V ₀ becomes negative.

On the other hand, the second detection circuit 231b of FIG. 9 performs switching with a phase shift of 90 degrees from that of FIG. 10B. Therefore, when the received signal Vin is in phase with the switching signal v as illustrated in FIG. 10A, the positive and negative portions of the received signal Vin are cut out by half, and the received signal is smoothed. Intensity signal V
_t (FIG. 9) becomes zero.

On the contrary, when the received signal Vin is the switching signal v
If when only the phase is shifted 90 degrees, the received intensity signal V _t from the second detection circuit 231b is a finite value, the reception strength signal V ₀ which from the first detection circuit 231a is zero.

As is well known in electronic circuit theory, when an arbitrary signal (here, received signal Vin) is expressed in a vector format in consideration of its phase, as shown in FIG.
It can be decomposed into components into two signal phase axes v and jv which are shifted by a degree, and if the two components are vector-combined, the absolute value and phase of the original signal Vin can be obtained.

[0074] In accordance with this principle, the vector combining section 240 in FIG. 9, two systems of output V ₀ which binary phase detection section 230,
The V _t to the vector synthesis. Specifically, the absolute value / phase calculation circuit 241 calculates

[0075]

## EQU1 ## The absolute value V of the reception voltage is obtained as the reception intensity according to V = (V ₀ ² + V _t ² ) ^1/2 , and the information θ regarding the phase of the reception voltage is calculated. Regarding the phase of the received voltage,

[0076]

[Number 2] _{θ = arctan (V t / V} 0) may be calculated, sufficient knowing whether the receive coil 11Y is deviated right or left direction in a horizontal plane with respect to the proper guidance direction in the device Therefore, the phase is expressed only by the positive and negative signs.

Here, FIG. 12 will be referred to as an example of how to determine the positive and negative signs. In the example of FIG. 12, assuming a two-dimensional phase space in which the phase of the signal v having the reference frequency f and the signal jv having a phase shifted by 90 degrees with respect to the coordinate axis are assumed, the composite vector of the received voltage is It is defined as "positive phase" when in the first or second quadrant and "negative phase" when in the third or fourth quadrant. However, regarding the vector on the jv coordinate axis, the positive direction of the jv axis is defined as “positive phase”,
The negative direction of the jv axis is defined as “negative phase”. Therefore, for example, when the received voltage vector is Ve shown in the figure, it has a positive phase, and when it is Vg, it has a negative phase.

When the polarity of such a phase is defined and the receiving coil 11Y is rotated in a horizontal plane, for example, the vector length is gradually increased from the state of Ve in FIG. (Absolute value), and the vector length becomes substantially zero in the proper guiding direction. Then, when the receiving coil 11Y is further rotated past the appropriate guiding direction, the vector starts to expand in the direction of Vg (the reverse direction of Ve), and then the vector length gradually reaches the state of Vg shown in the figure.

Therefore, when the direction of the receiving unit 10A incorporating each receiving coil is gradually changed from an arbitrary direction in the excavation guidance of the tunnel, a finite receiving voltage value is firstly observed in any polarity, and then, The voltage value gradually decreases and reaches a minimum value (ideally zero). The direction is the proper guiding direction, but when the proper guiding direction is exceeded, the voltage swings in the opposite polarity. Accordingly, it is possible to recognize that "the direction has been changed too much", and to return to the opposite direction, it is possible to finally specify the appropriate guidance direction.

[0080] When defining the polarity of the phase is as shown in FIG. 12, it may only sign of V ₀ component as information representing the phase. Only when the V ₀ component is zero, it is referred whether the V _t component is positive or negative. V ₀ component and V _t
When both components are zero, the absolute value is zero, so that the polarity is substantially the same regardless of the definition.

[0081] Specifically, the absolute value / phase calculation circuit 241 in FIG. 9, to determine the sign of V ₀ component and the V _t component according to the above criteria,

[0082]

## EQU00003 ## A phase signal .theta. Is generated such that .theta. = + 1 (in the case of a positive polarity phase) and .theta. =-1 (in the case of a negative polarity phase). However, it is sufficient that “+1” and “−1” here are mutually identified as logical values. In addition, since the case where the reception voltage vector is on the jv axis in FIG. 12 is only an exceptional case, the phase information θ may be obtained only by the sign of the in-phase component V ₀ .

FIG. 12 is merely an example, and it is possible to arbitrarily determine which half plane is “positive”. This is because it suffices that the polarity be reversed only across the appropriate guidance direction.

The received signal V and the phase signal θ shown in FIG. 9 are input to the logarithmic amplifier 250. The LOG amplifier 251 receives the reception intensity signal V and performs logarithmic amplification. This is to effectively use the dynamic range of the apparatus by expanding the scale of the area where the reception intensity is near the minimum value and compressing the scale in a direction far away from the scale. As a result, using a limited dynamic range, the range that deviates considerably from the effective proper guidance direction is rough, and the direction can be accurately detected when approaching the proper guidance direction.

The output of the LOG amplifier 251 is

[0086]

## EQU4 ## Even if the input is the square of the reception strength V, the output is log (V).

[0087]

## EQU5 ## It can only be doubled as in 2.log (V). Therefore, the number 1 described above
In the calculation of the absolute value of, the process of finding the square root may be omitted.

The logarithmically amplified signal is applied to the next-stage phase applying circuit 252, where the phase represented by the phase signal θ (the polarity of the phase in this example) is applied. Therefore, the final output of the logarithmic amplifier 250 is obtained by logarithmically converting the intensity of the received signal Vin and adding a sign corresponding to the phase.

By displaying this on the next meter 260, the intensity and phase polarity of the received signal Vin can be visually recognized. This information can be used for left-right direction guidance as well as position guidance.

The input buffer circuit 211 of the circuit components in FIG. 9 is provided in the receiving circuit section 12 in FIG. 5, but the portion from the narrow-wave tuning amplifier section 220 to the logarithmic amplifier section 250 is the receiving circuit section. 12 may be stored in the monitor unit 10M of FIG.

* <XZ induction> FIG. 13 is a diagram showing a circuit for detecting and inducing signals received by the second receiving coil 11a and the third receiving coil 11b.

First, the second receiving coil 11a and the third receiving coil 11a
The signals received by the receiving coil 11b are input buffer circuits 31 in the receiving coil units 310a and 310b, respectively.
The signals are respectively buffered and amplified at 1a and 311b.

Each of the received signals amplified in this manner is supplied to a narrow-wave tuning amplifier (band-pass filter) 320a, 320
b, the frequency component corresponding to the transmission frequency of the received signal (1 kHz in this embodiment)
(a component near z) is selectively transmitted. As a result, the noise component is cut off, and the signal becomes suitable for detecting the minimum reception intensity.

[0094] The received signal, which is essentially only the transmission frequency component in this manner, is transmitted to the next-stage two-phase detectors 330a and 330a.
30b. These two-phase detectors 330a,
The configuration and operation of 330b are the same as those in the two-phase detector 230 of FIG.
Is the same as

Therefore, one of the two-phase detectors 330a
From the phase reference signal v and the component V _at the in-phase component V _a0 opposite phase are output, from the other of the two phase detection unit 330b, a phase reference signal v in phase with the component V _b0 reverse phase Component V of
_bt is output.

In the next stage of the vector synthesis section 340, (1) the sum of the v components (V _a0 + V _b0 ) (2) the difference between the v components (V _a0 , V _at , V _b0 , V _bt ) V _a0 -V _b0) (3) the sum of jv component _{(V at + V bt) (} 4) the difference between the jv component (V _at -V _bt) the determined output.

Of these, the sum of the v components (V _a0 + V _b0 )
And the sum of the jv components (V _at + V _bt ) are provided to the absolute value / phase calculation circuit 342 at the next stage, and their vectors are synthesized, and as the absolute value of the vector sum,

[0098]

[6] _{Vz = [(V a0 + V} b0) 2 + (V at + V bt) 2] 1/2 is calculated. This becomes information for direction guidance in the vertical direction, and is also used for position guidance.

The difference between the v components (V _a0 −V _b0 ) and jv
The difference between the components (V _at −V _bt ) is given to the other absolute value / phase calculation circuit 343, and their vector synthesis is performed.
As the absolute value of the vector difference,

[0100]

Vx = [(V _a0 −V _b0 ) ² + (V _at −V _bt ) ² ] ^1/2 is calculated. This is used as assistance for direction guidance in the left, right, up and down directions, and is also information for position guidance.

The same applies to the phase. According to the definition described with reference to FIG.

[0102]

(8) θz = + 1 (when the vector sum has a positive polarity phase) θz = −1 (when the vector sum has a negative polarity phase)

[0103]

## EQU9 ## Phase polarity information such as θx = + 1 (when the vector difference has a positive polarity phase) θx = −1 (when the vector difference has a negative polarity phase) is obtained.

Among them, the reception intensity signal (absolute value signal) Vz and the phase polarity signal θz are supplied to the logarithmic amplifier 350 at the next stage.
Z, the logarithmic amplification of the reception intensity signal Vz is performed in the LOG amplifier 351Z, and the phase polarity represented by the phase signal θz is provided in the phase providing circuit 352Z.

Similarly, the other received intensity signal (absolute value signal) Vx and the phase polarity signal θx are compared with the logarithmic amplifier 350 at the next stage.
X, the logarithmic amplification of the reception intensity signal Vx is performed in the LOG amplifier 351X, and the phase polarity represented by the phase signal θx is provided in the phase providing circuit 352X.

Then, these are connected to the next-stage meter 360Z,
By displaying each of them at 360X, (a) the intensity and phase polarity of the received signal of the X coil and (b) the intensity and phase polarity of the received signal of the Z coil become visible.

The input buffer circuits 311a and 311b of the circuit components of FIG.
, The narrow-wave tuning amplifiers 320a and 320b
1 to the logarithmic amplifiers 350Z and 350X may be housed in the receiving circuit unit 12 or may be housed in the monitor unit 10M in FIG.

Further, the modifications made in the description of the circuit of FIG. 9 can be applied to the circuit of FIG.

* <External Example of Monitor Unit 10M> FIG. 14 shows an external example of the monitor unit 10M. The monitor unit 10M has the meters 260, 360X, and 360Z described in FIGS. 9 and 13 arranged on the upper surface of the casing CS. In addition, other operation switches such as a power switch and various display units are arranged together.

Taking the meter 260 as an example, there is a zero point at the center and plus and minus voltage indicating scales on the left and right. The same applies to other meters.

In the vicinity of each meter, a criterion for directional guidance is displayed in characters. In the example of the meter 260, it is shown that the direction is read as a left-right direction guidance display when searching for a direction, the direction of the minimum value is searched, and the same applies to the position guidance (point guidance) to the target point. Have been. Regarding the meters 360Y and 360Z, whether to look at the maximum value or the minimum value of the meter reading differs between the direction guidance and the position guidance.

* <Excavation Guidance Method> The excavation path guidance apparatus having the above configuration can be used as follows.

First, the underground transmission unit 2 arranged as shown in FIG.
An electromagnetic wave is radiated from the transmission coil 21 during 0A for a certain period (for example, about 10 seconds). As described above, the electromagnetic wave from the underground transmitter 20A specifies the direction in which the tunnel 1 is to be guided with reference to the excavation plan of the tunnel 1 and is emitted toward it. The azimuth at the installation position of the transmission unit 20A may be specified by a compass or other known means.

When such transmission is performed, tunnel 1
It is received by the receiving unit 10A installed behind the excavator 2 in the inside, and among the meters in the monitor unit 10M (FIG. 14), in particular, the display of the meter 260 for the left-right guidance and the meter 360Z for the vertical guidance are shown. Focus on the state.

The operator observes these meters of the monitor section M, and the receiving section until both the left-right guidance meter 260 and the vertical guidance meter 360Z reach their minimum values (ideally zero). By remotely operating the drive mechanism 2D and slowly swinging the receiving unit 10A right and left and up and down, an appropriate guiding direction at that point is searched. The direction of the maximum value of the remaining meter 360X can be used as an aid in that case.

When such a proper guiding direction is found, the body of the excavator 2 is remotely operated to guide the excavating direction in the proper guiding direction. Since the display on the monitor unit 10M has a plus / minus polarity sign, when searching for a proper guidance direction, if the vehicle passes through the proper guidance direction when viewed from the side where the swing rotation is started, the opposite polarity direction of the meter is used. Therefore, it can be immediately known that such a passing has occurred, and the returning operation can be performed early.

During the subsequent excavation work, it is monitored whether or not the excavation in the appropriate guiding direction is being performed by referring to the monitor unit 10M as appropriate. If the deviation is likely to occur, the guiding direction is corrected.

On the other hand, an electromagnetic wave is radiated in a substantially vertical direction from the ground surface transmitting unit 30A into the ground during a period different from the transmission for such direction guidance. And the meter 2 in the Y direction
If the intensity of the meter 60X and the meter 360X in the X direction reaches the minimum value (substantially zero) and is found to be immediately below the ground reference position RP, the excavation is temporarily stopped. In this case, Z
It is possible to additionally use whether the indication of the direction meter 360Z is maximized.

Then, a new reference position is set, and the same operation can be performed using the electromagnetic wave from the new reference position.

Here, the direction guidance and the position guidance are performed separately in order to avoid interference between the electromagnetic wave from the underground transmission unit 20A and the electromagnetic wave from the ground surface transmission unit 30A. When the transmission and reception frequencies are shifted, the transmission may be performed simultaneously and the respective wavelengths may be separated.

When the excavation direction is changed, a boring pit similar to the boring pit 5 in FIG. 1 is dug in the next target direction, the underground transmitting section 21A is moved there, and a new excavation arrival is performed. Move the ground surface transmitter 31A to the target point,
Excavation guidance similar to the above may be performed.

* <Advantage of Detection of Minimum Value of Received Signal Strength> As described above, the receiving coil 11Y is
(Accurately, the receiving unit 10A arranged in the vicinity of the face 3) mainly uses the fact that the receiving intensity is minimized when the direction matches the proper guiding direction. The excavation may be guided by detecting the direction in which the reception intensity becomes maximum with reference to the reception voltage of the extending reception coil. In fact, in the device of this embodiment,
In the direction guidance, the X coil (X of the vector receiving coil V)
(Component) is used as a supplement.

The reason why the detection of the maximum intensity is used only as an auxiliary is that the detection of the minimum intensity is more advantageous in the detection processing itself, such as increasing the sharpness in specifying the appropriate guidance direction. This is because there is an advantage that the effect of logarithmic amplification and the like are large and suitable for displaying a detection result. The reason is as follows.

First, as for the point (1), it is assumed that the coil 11X has a coil axis oriented in the X direction as shown in FIG. 15 and the maximum intensity of the received voltage is detected. At this time, the receiving coil 11X moves in the vertical plane with the arrow RT.
Consider a state ZS inclined as shown in FIG. In this case, the magnetic flux passing through the receiving coil 11X is different from the case where the receiving coil 11X is horizontal. That is, in the case of such a configuration, when the receiving coil 11X provided for direction guidance in the horizontal plane is inclined in the vertical in-plane direction, not only the magnetic flux component in the horizontal plane but also the vertical The magnetic flux component also affects the received signal. For this reason, in the case of such a configuration, sharpness in specifying the direction in which the reception voltage becomes maximum is not so high.

On the other hand, as shown in FIG.
Assuming that the axis of 1Y is the Y direction, the axial direction of the receiving coil 11Y does not substantially change even if the receiving coil 11Y is inclined as indicated by the arrow RT in the vertical plane. On the other hand, the receiving coil 11Y in another vertical plane in FIG.
Is inclined, the coil axis of the receiving coil 11Y is inclined in that direction. However, also in this case, since the total magnetic flux amount passing through the receiving coil 11Y in the state of FIG. 16 does not substantially change due to the symmetry (rotation symmetry) of the magnetic flux distribution, there is no substantial effect due to this inclination.

As described above, in the configuration shown in FIG. 16, there is no substantial effect due to the inclination of the receiving coil 11Y in the vertical plane, and the appropriate guiding direction in the horizontal plane is determined particularly sharply. That is, in order to more accurately perform direction guidance in a horizontal plane by eliminating the influence of the vertical tilt, it is preferable to capture the direction in which the received signal is minimized. Here, the direction guidance in the horizontal plane was considered, but the same applies to other direction guidance and position guidance.

This situation can be further understood from FIG. FIG. 17 is a diagram schematically illustrating the direction dependency of how the intensity of the reception voltage changes when the reception coil is oriented in each direction. However, FIG.
In the above, the sign of the received signal is given a positive or negative sign in consideration of the polarity of the received signal.

The direction distribution of the magnetic flux due to the electromagnetic wave emitted from the transmission coil can be approximately expressed by a trigonometric function. In the vicinity of the maximum intensity direction, there is an even symmetry like a cosine function, and the rate of change of the reception intensity with respect to a slight deviation from the maximum intensity direction is small.

Therefore, in the case of detecting the maximum intensity direction, the sharpness in the detection is low, and in the state shifted from the maximum intensity direction, it is determined to which side the maximum intensity direction is shifted. Since it is impossible, only the absolute value of the reception intensity is known.

On the other hand, when the minimum intensity direction is configured to be detected, the sine function has an odd symmetry near the minimum intensity direction as shown in FIG. The rate of change of the reception intensity with respect to the deviation is large. For this reason, the sharpness in the detection is high, and in the state shifted from the direction of the minimum intensity, it is possible to distinguish to which side from the direction of the minimum intensity by the polarity of the received signal.

These are the first advantages mainly using the detection of the minimum direction of the reception voltage.

Regarding the above-mentioned corresponding to the second advantage, when the detection is performed near the maximum reception intensity, the difference near the maximum value is amplified and the dynamic range of the amplifier is increased even if an attempt is made to display the difference in detail. And the output is saturated. On the other hand, the minimum voltage near zero intensity can be sufficiently amplified, and if logarithmic amplification is performed as described above, the vicinity of the minimum value (zero intensity) corresponding to the appropriate guiding direction is detailed and considerably reduced from the minimum value. Large, distant portions can be displayed roughly. This is particularly suitable for the direction guidance operation in tunnel excavation in which the direction is roughly adjusted to the vicinity of the appropriate guidance direction, and then the direction of the receiving unit 11A is slightly changed to determine the appropriate guidance direction.

For the above reasons, the device of this embodiment is configured to perform guidance using the minimum value of the reception voltage as an index.

* <Main Effects and Modifications According to Embodiment> As described above, in the method according to the present embodiment, the reference position is determined through the emission of electromagnetic waves in the radio waveband from the reference position and the detection thereof near the face 3 And the spatial relationship between the face and
As a result, excavation guidance is performed, so that excavation guidance can be efficiently performed regardless of whether straight excavation or curved excavation is performed.

[0135]

When the monitoring unit 10M is placed in the tunnel of the tunnel 1, the operation of changing the direction of the receiving unit 10A may be performed manually in order to search for an appropriate guiding direction. Further, by providing the output signal of the receiving unit 10A to the propulsion control unit of the excavator 2, it is possible to perform automatic control such that the excavation is always performed in the appropriate guidance direction.

That is, the method of controlling the excavator 2 after detecting the appropriate guiding direction and specifying the direction in which the excavation proceeds is arbitrary.

Further, it is preferable to use an electromagnetic wave having directivity as in the above-described embodiment. Since the received voltages are different, the principle of direction guidance is not hindered.

Further, if boring holes are excavated at a plurality of reference positions apart from each other, and electromagnetic waves from the boring holes are received by the face, not only the direction but also the two-dimensional or three-dimensional shape of the face can be obtained by the principle of triangulation. Position can be specified. Also in this case, the electromagnetic waves may be emitted from the respective boring holes with a time lag, or transmitted and received at the same time by changing the wavelength.

[0140]

As described above, in the method of the present invention, the direction and position of the face can be confirmed by using high-frequency electromagnetic waves that can propagate in the ground. In addition, even in curved excavation, the guidance of the excavation path can be accurately performed.

Further, since it is only necessary to receive an electromagnetic wave near the face, unlike the second prior art, when the liner moves in the curved excavation, it is not necessary to install a reflecting mirror or a laser transmitting / receiving device again. For this reason, work time and manpower are reduced, and efficient excavation path guidance is possible.

In particular, in the second aspect of the present invention, the direction and position of the face are more accurately specified by using the electromagnetic wave having directivity.

According to the third aspect of the present invention, since the reference position is the underground position, it is particularly effective for confirming the straightness in that direction.

In the invention of claim 4, since the reception intensity of the electromagnetic wave is minimized in the direction toward the underground position, it is easy to amplify the reception signal without increasing the dynamic range. There are advantages too.

According to the fifth aspect of the present invention, since the reference position is the ground surface position, it is particularly effective for confirming the reachability immediately below the ground surface position.

[0146]

[0147]

The invention according to claim 6 and claim 7 is an apparatus suitable for carrying out the method according to claim 1 or the like.

[0149]

[Brief description of the drawings]

FIG. 1 is a diagram showing an example of a situation to which an embodiment of the present invention is applied.

FIG. 2 is a schematic plan view showing only a portion related to a transmitting unit and a receiving unit of the electromagnetic wave when seeing FIG. 1 from above;

FIG. 3 is a configuration diagram illustrating an outline of an internal configuration of an underground transmission unit 20A.

FIG. 4 is a configuration diagram illustrating an outline of an internal configuration of a ground surface transmission unit 30A.

FIG. 5 is a perspective view illustrating an outline of an internal configuration of a receiving unit 10A.

FIG. 6 shows a transmitting coil 21 disposed underground and a receiving unit 10
It is the schematic diagram which looked at the positional relationship with the receiving coil 11Y inside from above.

FIG. 7 shows a transmitting coil 31 arranged on the ground surface and a receiving unit 10
It is the schematic diagram which looked at the positional relationship with the vector receiving coil 11V in the middle from the upper part.

FIG. 8 is a diagram showing a circuit configuration of an underground transmission unit 20A and a ground surface transmission unit 30A.

FIG. 9 shows a first receiving coil 11Y of the receiving unit 10A.
FIG. 3 is a circuit diagram showing a part for detecting and displaying a signal received by the control unit.

FIG. 10 is a waveform chart showing the principle of phase detection of a received signal.

FIG. 11 is an explanatory diagram of phase decomposition of a received signal.

FIG. 12 is an explanatory diagram for defining a phase polarity.

FIG. 13 shows a vector receiving coil 1 of the receiving unit 10A.
FIG. 3 is a circuit diagram showing a part for detecting and displaying a signal received at 1V.

FIG. 14 is a diagram illustrating an example of the appearance of a monitor unit 10M.

FIG. 15 is an explanatory diagram in the case of a configuration in which the maximum intensity of the reception voltage is detected.

FIG. 16 is an explanatory diagram of a case in which a minimum intensity of a reception voltage is detected.

FIG. 17 is an explanatory diagram for comparison between detection of the maximum intensity of the reception voltage and detection of the minimum intensity.

[Explanation of symbols]

 Reference Signs List 1 tunnel 2 excavator 3 face 10A receiving unit 10M monitoring unit 30A ground surface transmitting unit 20A underground transmitting unit 11Y receiving coil 11V vector receiving coil 250, 350Z, 350X logarithmic amplifier 260, 360Z, 360X meter

──────────────────────────────────────────────────続 き Continuing on the front page (72) Mitsuyo Yoshimoto 3-3-22 Nakanoshima, Kita-ku, Osaka City, Osaka Prefecture Kansai Electric Power Co., Inc. (72) Yoshinori Higashi 1-13-4 Miyamae, Sakura City, Chiba Prefecture (56) References JP-A-4-336196 (JP, A) JP-A-5-79281 (JP, A) JP-A-64-42415 (JP, U) (58) Fields investigated (Int. Cl. ⁷⁾ , DB name) E21D 9/06 311 G01B 7/00

Claims (7)

(57) [Claims] 1. A method of guiding a tunnel excavation path in a propulsion method, comprising: a step of guiding a tunnel excavation path at a reference position in front of a tunnel excavation direction; Transmitting the electromagnetic field of the band, receiving the electromagnetic wave near the face of the tunnel excavation path to obtain a received signal, performing phase detection of the received signal to calculate the absolute value and phase polarity of the received signal, The spatial relationship between the tunnel excavation path and the reference position is specified by an amount having a magnitude according to an absolute value and a sign according to the phase polarity, and guiding the tunnel excavation path based on the spatial relationship. A method for guiding a tunnel excavation path. 2. The method according to claim 1, wherein an electromagnetic wave having directivity is used as the electromagnetic wave. 3. The method according to claim 2, wherein the reference position is set to an underground position. 4. The method according to claim 3, wherein the transmitting coil is arranged at the underground position with a direction in which the tunnel excavation path is to be guided as a coil axis direction, and the electromagnetic wave is received by a receiving coil arranged near the face. A tunnel excavation path guidance method, characterized in that the direction of the receiving coil axis at which the receiving intensity of the receiving coil is minimized by receiving is perpendicular to the direction toward the underground position. 5. The method according to claim 2, wherein the reference position is set to a ground surface position. 6. Guiding a tunnel excavation path in a propulsion method
Apparatus for it, can be installed in front of the reference position of (a) a tunnel excavation direction
Yes, the direction to guide the tunnel excavation path is the coil axis
A transmission coil that transmits an electromagnetic field in the radio waveband as the direction
And transmitting means including, (b) receiving the electromagnetic wave in the vicinity of the working face of the tunnel boring path
Detecting the absolute value and phase polarity of the received signal of the electromagnetic field.
Receiving means, (c) having a size according to the absolute value and
A display means for displaying a quantity having a sign according to the phase polarity
Tunneling path guiding device, characterized in that it comprises a stage, a. 7. The apparatus according to claim 6, wherein said transmitting means comprises: (a-1) said transmission means is disposed at a first reference position underground;
The coil axis is aligned with the direction Y to guide the excavation path.
(A-2) a transmission coil (21) located at a second reference position on the ground and in a vertical direction Z
A second transmission coil (31) provided with a capital, it said receiving means, which is matched to the coil axis and (b-1) horizontal coil (11Y), (b-2) the horizontal coil (11Y) Vertical face
(XZ) and V whose symmetry axis is the vertical direction Z
Includes a type coil (11V), and the display means, the received signal (c-1) the horizontal coil (11Y), the
The first mail that is displayed with a plus / minus sign corresponding to the phase polarity
(260) and (c-2) the vertical composition of the reception signal of the V-shaped coil (11V).
Minutes are displayed with a sign according to their phase polarity.
(C-3) a second meter (360Z) of the V-shaped coil (11V);
Minutes are displayed with a sign according to their phase polarity.
That a third meter (360X), tunnel boring path guiding device, characterized in that it comprises a.