JPH10206557A - Method for detecting position of underground buried object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To specify a corresponding ground burial position by burying an information display by matching the directions of its dialing signal and a generation electromagnetic wave, moving a recognition means horizontally along the ground, and obtaining the signal output in vertical direction of each position. SOLUTION: An information display 1 is buried by matching the directivity of a transmission signal to that of an electromagnetic wave that a transmission antenna coil 3 generates. The information generator 1 generates a magnetic flux line 5 in response to the generated electromagnetic wave of a transmission antenna coil 3 and receives it by a reception antenna coil 6. The information display 1 is buried with a directivity that is perpendicular to a ground surface 2 and the reception antenna coil 6 is moved horizontally along the ground surface 2. A generated current by the magnetic flux line 5 of the reception antenna coil 6 is the strongest when the ground-corresponding position of the information display 1 matches the center position of the reception antenna coil 6 and becomes weak as they are separated, thus accurately detecting the position of the information display 1 and specifying the ground surface position with less error.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to the marking of the location of various underground objects such as land, roads and buried pipes, and various kinds of information on the site. It can also be used for surveying and infrastructure related systems.

[0002]

2. Description of the Related Art The location of underground objects such as gas pipes and water pipes,
That is, as a method for detecting the ground-corresponding position, Japanese Patent Publication No. 7-86
No. 533 proposes a method in which a current is caused to flow through a conductive underground object by electromagnetic induction, and a magnetic field generated by the induced current is detected to detect the position of the underground object.

Further, Japanese Patent Application Laid-Open No. Hei 7-306044 proposes a sign provided by providing a recording member capable of reading position information and the like on an installation position information sign.

[0004]

The former technique is a method of detecting the position of an underground object, in which a transmitter variably configures a magnetic flux linkage state with respect to an underground object, and a magnetic field distribution is controlled by a receiver. Measure and change the state of magnetic flux linkage while detecting the deviation between this and the predetermined cylindrical magnetic field distribution, adjust the transmitter to minimize this deviation, and determine the target according to the measured magnetic field distribution at this time. This is to detect the position of the underground buried object. When this method is used, there is a problem that it is not possible to discriminate between a water pipe and a gas pipe, and it is not possible to detect when the pipe material is PVC or the like. Further, when measuring the magnetic field distribution, the detection area of the magnetic sensor has an extension, so that the position cannot always be specified with high accuracy.

In the latter technique, the position information and the like are inserted into a sign to determine the position information and the like. However, when the recording member is buried deep underground, the detection of the recording member spreads over the detection area of the receiver. Therefore, even if the position information or the like is found, it is impossible to specify the actual position except for the case where the sign is peeped on the ground surface.

The present invention has been made in view of the above points, and the present invention avoids the effect of attenuation on the detection distance of electromagnetic waves generated from an antenna of a transmitter, and has only one directivity. In order to improve the drawback of the method of detecting the position of an underground object using only one information indicator, that is, the position corresponding to the ground surface corresponding to the position of the underground object buried considerably deep is raised. It is an object of the present invention to provide a detection method capable of detecting with high accuracy and having distinctiveness.

[0007]

In order to achieve the above-mentioned object, an electromagnetic wave generating means for generating an electromagnetic wave typified by an antenna of a transmitter is buried in the ground, so that the influence on the detection distance of the electromagnetic wave generated is reduced. Focusing on the disappearance and the directionality of the electromagnetic waves generated by the information display,
As a result of intensive studies on high-accuracy position detection, the present invention has been achieved.

That is, the present invention provides an electromagnetic wave generating means (1) buried in the ground to generate an electromagnetic wave having directivity, and responds by electromagnetic induction of the electromagnetic wave from the means (1).
An information display (2) buried in the ground for generating a signal having directivity, and a movable recognition for detecting a signal generated from the display (2) and recognizing each signal output. Means (3), wherein the information display (2) is
It is buried in the ground so that the directivity of the signal transmitted from the display (2) matches the directivity of the electromagnetic wave generated from the means (1), and the means (3) is horizontally moved along the surface of the ground. By means of the movement, the means (3) obtains a signal output value in the vertical direction on the ground surface at each movement position, and specifies a ground surface buried position corresponding to the ground buried position of the information display (3). An object of the present invention is to provide a method for detecting the position of an embedded object. (Hereinafter, referred to as a first invention)

Specifically, the information display (2) is selected from the following information displays.

(A) LC resonance circuit marker. (B) An electromagnetic induction type marker composed of a semiconductor memory element, a communication / memory control element, and a frequency transmission / reception element and recorded with position information and the like. (C) A magnetic pattern corresponding to a bias magnetic field mechanically resonates with a magnetized bias magnetic field generating element at a specific frequency in an incident alternating magnetic field of a fluctuating frequency to change a magnetic flux density or a magnetic permeability. A marker in which a specific frequency at which a magnetic flux density or a magnetic permeability changes is generated as position information or the like, wherein the highly permeable metal is laminated so as to be able to resonate mechanically.

Alternatively, an electromagnetic wave generating means (1) for generating electromagnetic waves having at least two directivities buried in the ground, and buried in the ground which responds by electromagnetic induction of electromagnetic waves from the means (1). An information display (2) for generating a signal having at least two directivities; and a movable recognition means for detecting a signal generated from the display (2) and recognizing each signal output ( 3) The information display (2) is buried in the ground so that the directivity of a signal transmitted from the display (2) matches the directivity of an electromagnetic wave generated from the means (1). Then, by moving the means (3) in the horizontal direction along the surface of the ground, the means (3) allows the display (3) to move in the same horizontal direction as the vertical direction on the surface of the directivity of the indicator (3) at each position of movement. The signal output value of With where the ratio of the signal output value is the maximum value, specifying the surface embedded position corresponding to the underground position of the information display (3), provides a position detection method for underground buried object. (Hereinafter referred to as the second invention)

Specifically, the signal output of the electromagnetic wave generated from the information display device has at least two directivities, any one of the following information display devices selected from the following, or the following having only one directivity: It is obtained by a combination of at least two information indicators selected from information indicators, which may be the same or different.

(A) LC resonance circuit marker. (B) An electromagnetic induction type marker composed of a semiconductor memory element, a communication / memory control element, and a frequency transmission / reception element and recorded with position information and the like. (C) A magnetic pattern corresponding to a bias magnetic field mechanically resonates with a magnetized bias magnetic field generating element at a specific frequency in an incident alternating magnetic field of a fluctuating frequency to change a magnetic flux density or a magnetic permeability. A marker in which a specific frequency at which a magnetic flux density or a magnetic permeability changes is generated as position information or the like, wherein the highly permeable metal is laminated so as to be able to resonate mechanically.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, as the electromagnetic wave generating means (1), a known and commonly used one can be employed. Usually, a transmitting antenna coil and an oscillator, a power supply and an amplifier for generating an electromagnetic wave therefrom are used. It is connected and configured as mandatory. If necessary, means for phase adjustment and noise removal can be included. The electromagnetic wave from the oscillator is emitted from the transmitting antenna coil toward the display (2). Preferably, only the transmitting antenna coil of the electromagnetic wave generating means (1) is buried in the ground. The transmitting antenna coil is embedded so that an electromagnetic wave having directivity emitted therefrom reaches the display (2).

On the other hand, the movable recognizing means (3) moves the ground surface in which the indicator (2) is buried horizontally along the ground surface, detects a signal generated thereby, and recognizes a signal output. . As the movable recognizing means (3), known ones can be adopted, but usually, a receiving antenna coil for detecting a signal output and a device (spectral analyzer) capable of detecting a resonating frequency and measuring an amplitude of a response signal. ) And a detection device for specifying a ground surface position corresponding to the buried underground position (ground buried position) including a power supply and an amplifier are indispensably connected. If necessary, the detection device can include a computer for performing data processing based on the signal output value obtained as described above, and comparing the data processing result with a database relating to buried position information and specifying the position. In addition, all the devices constituting the recognition means (3) (whole)
May be movable, but of the means (3), it is preferable from the viewpoint of workability that only the receiving antenna coil is movable.

The information display (2) may be represented by numeral 11 or numeral 12 in the description used in the drawings. The display (2) will be described later in detail.

Next, the operation of the present invention will be described. The intensity of the electromagnetic wave generated from the information display (2) depends on the intensity of the electromagnetic wave applied from the transmission antenna coil of the electromagnetic wave generation means (1) and the distance between the transmission antenna coil and the information display (2). Further, the signal output of the receiving antenna coil of the movable recognizing means (3) depends on the strength of the electromagnetic wave generated from the information display (2) and the distance from the receiving antenna coil.

In particular, in the case of the induced electromagnetic field, the intensity of the electromagnetic wave depends on the distance, and is proportional to the reciprocal of the square of the distance according to Biot-Savart's law. Therefore, in the case of a transmission / reception-integrated antenna coil, the distance between the information display device and the antenna coil cannot be more than a certain distance. Specifically, tens of cm
The above reading distance cannot be obtained. The present inventors have noticed that the signal of the information display (2) can be efficiently picked up by the reception antenna coil by bringing the transmission antenna coil closer to the information display (2). Furthermore, it has been found that by winding the transmission antenna coil around the information display, a signal of the information display can be obtained efficiently with low power.

More specifically, an example of a method of detecting the position of an underground buried object for specifying the underground buried position corresponding to the underground buried position according to the present invention will be described with reference to FIGS. In the figure, reference numeral 1 indicates an information display (2), reference numeral 2 indicates the ground surface, and reference numeral 3
Denotes a transmitting antenna coil as an example of the electromagnetic wave generating means (1), and reference numeral 4 denotes an oscillator, a power supply, and the like for generating an electromagnetic wave in the transmitting antenna coil. X indicates when the directivity of the information display 1 is perpendicular to the ground, and Y indicates when it is parallel to the ground.

The information display (2) is designed such that the directivity of the signal to be transmitted from it coincides with the directivity of the electromagnetic waves to be generated from the means (1), in particular from the transmitting antenna coil. Buried.

The power supply 4 is connected to a transmission antenna coil buried underground by a conductor. These need not always be connected and energized, and may be connected as needed when connection is detected on the ground surface.
The transmitting antenna coil and the information display (2) need only be in a positional relationship such that the electromagnetic wave emitted from the former reaches the latter, and effective detection can be performed even if the output of both is smaller. Preferably, the former is buried adjacent to the latter.

The shape of the transmitting antenna coil of the present invention for generating the electromagnetic wave of the means (1) is preferably a loop antenna, and a copper wire or the like is formed in a circular or rectangular shape around the center line of the directivity of the information display (2). It is preferable that the wire is wound around the information display (2) for one or more turns. Also, if the transmitting antenna coil is formed by increasing the number of turns of a copper wire or the like to form a solenoid coil and inserting the information display (2) therein, a large electromagnetic wave with low power can be applied to the information display (2). Are particularly preferred.

Reference numeral 5 denotes a magnetic flux line generated by the information display (2) in response to an electromagnetic wave emitted from the transmitting antenna coil of the means (1), which is indicated by a dotted arrow. Reference numeral 6 denotes a receiving antenna coil which is an example of a recognizing means (3) for detecting a signal emitted from the information display (2) and recognizing the signal as a signal output. The receiving antenna coil receives a directional electromagnetic wave. The coil is preferably a loop antenna, and is preferably a coil in which a copper wire or the like is wound in a circular or rectangular shape for one or more turns, or a center feed loop coil.

The electromagnetic wave generated from the transmitting antenna coil and applied to the information display (2) has a low impedance in the near field, the magnetic vector is dominant, and the energy is composed of a magnetic field component and a slight electric field component. The directivity of electromagnetic waves is particularly high at frequencies higher than the microwave range, but when penetrating deep into soil containing moisture, long-wave electromagnetic waves are preferred. Therefore, the operation will be described with respect to the magnetic field component of the electromagnetic wave, that is, the case of the AC magnetic field.

FIG. 1 shows that only one information indicator (2) having a single directivity is buried in the ground so as to have a directivity, and the signal output recognition means (3) is movable. The antenna coil moves horizontally along the ground surface, that is, parallel to the ground (thick dotted arrow).

The information display (2) having the directivity X generates a magnetic flux line 5 having a vertical directivity on the ground in response to the applied magnetic energy, and as shown in FIG. It is detected by the antenna coil. The current generated when the magnetic flux lines 5 are cut by the receiving antenna coil from the directivity X information display (2) is located at the center of the receiving antenna coil at the position corresponding to the ground surface of the directivity X information display (2). When the information is matched, the current flows most strongly, and the flowing current becomes weaker as the position of the information display (2) shifts away from the center position of the receiving antenna coil and moves away.

FIG. 2 shows a state in which only one information indicator (2) having a single directivity is buried with directivity Y parallel to the ground, and the receiving antenna coil moves parallel to the ground. (Thick dotted arrow).

The information display (2) having directivity Y generates magnetic flux lines 5 'having directivity parallel to the ground, and the magnetic flux lines 5' are detected by the receiving antenna coil of the magnetic flux lines. The current generated when the magnetic flux line 5 'from the information indicator (2) of the directivity Y is cut by the receiving antenna coil is located at the center of the receiving antenna coil at the position corresponding to the ground of the information indicator (2). The value of the current flowing when the value of the information display coincides shows a minimum, and the current flowing increases as the position of the information display device shifts away from the center position of the receiving antenna coil and moves away, and the position of the information display device (2) corresponds to the ground. It shows the maximum of the current value in the vicinity of several tens centimeters from the position, and then gradually decreases.

Next, a case will be described in which two types of information indicators (2) having different directivities are buried in the ground.
FIG. 3 shows a case where two information displays (2) having only one directivity are used in combination for convenience.
FIG. 3 shows two kinds of directivities of the information display (2) such that one directivity is vertical to the ground (directivity X) and the other directivity is parallel to the ground (directivity Y). Thus, the information display (2) is embedded, and the receiving antenna coil moves parallel to the ground.

As will be described later, it is preferable that the electromagnetic wave having directivity X and the electromagnetic wave having directivity Y generated by the information display (2) can be received without interference with each other. More specifically, for example, the frequency and the modulation method may be different, and another method may be used as long as there is a means for identification.

The information display 11 generates a magnetic flux line 5 having a vertical directivity on the ground, and is detected by a receiving antenna coil as shown in FIG. The current generated when the magnetic flux lines 5 are cut by the receiving antenna coil from the information display 11 is located at the center of the receiving antenna coil.
When the position of the information display 11 coincides, the current flows most strongly, and as the information display 11 is shifted to the center position of the receiving antenna coil and moves away, the current flowing becomes weaker.

On the other hand, the information display 12 generates a magnetic flux line 5 'having directivity parallel to the ground, and is detected by the receiving antenna coil as shown in FIG. The current generated when the magnetic flux line 5 'from the information display 12 is cut by the receiving antenna coil indicates that the current flowing when the position of the information display (2) coincides with the center position of the receiving antenna coil is minimal. As the position of the information display 12 shifts away from the center of the receiving antenna coil and moves away, the flowing current increases, shows a local maximum of the current value in the vicinity of several tens of centimeters from the center of the receiving antenna coil, and gradually thereafter. To decline.

Therefore, the reception antenna coil of the recognizing means (3) for recognizing the signal output, the signal output value emitted from the information display (2) at the position where the reception antenna coil exists, and the signal output value in the vertical direction on the ground surface, And the signal output value in the horizontal direction can be obtained on the ground surface. Therefore, by moving the signal output recognition means (3) horizontally along the ground surface on which the information display (2) is buried, a set of signal output values is obtained for one measurement position.

In the present invention, the ratio between the two, that is, the signal output value in the vertical direction on the ground surface and the signal output value in the horizontal direction on the ground surface at the measurement position obtained from the receiving antenna coil, is used. "Vertical signal output value on the ground /
The horizontal signal output value on the ground surface is determined.

Thus, the signal output recognizing means (3)
Is moved, and the above-mentioned ratio at each measurement position can be obtained by measuring the above-mentioned signal output values at several positions.

When the ratio between the information display device 11 and the information display device 12 is taken, the local minimum appears around several tens of centimeters from the center of the receiving coil, and theoretically the ratio becomes maximum at the center of the receiving antenna coil. , The ratio increases toward the center of the receiving antenna coil, and reaches a maximum value at the center of the coil.

In particular, since the rate of increase in the ratio near the center of the coil is large, the position of the information display (2) can be specified with extremely high accuracy.

By plotting the ratio based on each signal output value for each measurement position on, for example, graph paper, it becomes clear at which measurement position the ratio becomes the maximum. In addition, it is possible to specify the ground surface buried position corresponding to the underground buried position of the underground buried object.

If the measuring accuracy of the recognizing means (3) is constant, it is natural that the position can be specified with higher accuracy by increasing the number of measuring positions required for specifying the position as much as possible.

Next, the information display (2) used in the present invention will be described. As this indicator (2),
A signal generator that generates a signal having one or more directivities can be used. As described above, a marker having a signal having only one directivity and a marker having a signal having at least two different directivities can be used.

(A) LC resonance circuit marker. (B) An electromagnetic induction type marker composed of a semiconductor memory element, a communication / memory control element, and a frequency transmission / reception element and recorded with position information and the like. (C) A magnetic pattern corresponding to a bias magnetic field mechanically resonates with a magnetized bias magnetic field generating element at a specific frequency in an incident alternating magnetic field of a fluctuating frequency to change a magnetic flux density or a magnetic permeability. A marker in which a specific frequency at which a magnetic flux density or a magnetic permeability changes is generated as position information or the like, wherein the highly permeable metal is laminated so as to be able to resonate mechanically.

As the information display (2), a marker constituted by an electric resonance circuit such as an LC resonance circuit or a crystal resonance circuit as in the above (A) can be used. L
The C resonance circuit is a circuit system including a coil and a capacitor, and the direction perpendicular to the coil surface becomes directional. Therefore, the information display (2) of the present invention may be configured by combining markers of LC resonance circuits having different resonance frequencies.

Alternatively, a marker using a non-contact communication medium of the electromagnetic induction type as described in (B) can be used. That is, a marker having a non-contact transmission and reception function and including a semiconductor memory element, a communication control unit, and a memory control unit can be used. Communication medium is several hundred KHz
In the following induction electromagnetic fields, coils are used for transmission and reception functions. The information display of the present invention may be made by combining markers of different information that can be identified by the direction perpendicular to the coil surface being directional.

Alternatively, the magnetic pattern corresponding to the bias magnetic field as described in (C) mechanically resonates with a magnetized bias magnetic field generating element at a specific frequency in an incident alternating magnetic field having a fluctuating frequency, thereby obtaining a magnetic flux density. Or the permeability changes,
It is possible to use a magnetic marker in which a highly permeable metal having a magnetostrictive property is laminated so as to be able to resonate mechanically, and a specific frequency at which a magnetic flux density or a permeability changes is generated as position information or the like. In particular, the highly permeable metal having magnetostriction is preferably in a strip shape, and when the magnetic pattern is magnetized in the long side direction of the strip, the long side direction becomes directivity. Therefore, the information display (2) of the present invention may be formed by combining magnetic markers having different mechanical resonance frequencies.

As described above, the information display (2)
The same type of markers can be combined from (A) to (C). The magnetic marker (C) is electrically L
Although the resonance frequency band is equivalent to that of the C resonance circuit, the frequency band of the resonance frequency of many of the markers (A) of the LC resonance circuit is higher than the microwave, whereas the magnetic marker (C) has a low frequency from the long wave to the medium wave. Assuming that the electromagnetic wave penetrates a layer containing water such as puddles and fallen leaves when the medium is assumed, long waves to medium waves are preferable, and the magnetic marker (C) is excellent.

The marker (B) using a non-contact communication medium of the electromagnetic induction type uses a long wave to a medium wave, but a marker having a power source such as a battery is buried in the soil. Have the problem of lack of persistence. Those that do not have a power supply modulate the carrier and carry the information, so the reading distance is shorter than the magnetic marker (C) that is identified by the presence or absence of the resonance frequency, and the price is also lower than the magnetic marker (C). Expensive.

Further, the information display may combine different types of markers. For example, the magnetic marker (C) and the marker (A) of the LC resonance circuit can be combined. In order to add an information amount, the marker (A) of the LC resonance circuit and the marker (B) using the non-contact communication medium of the electromagnetic induction type can be combined. Alternatively, the magnetic marker (C) and the marker (B) using a non-contact communication medium of the electromagnetic induction type can be combined.

In any case of the LC resonance circuit and the non-contact communication medium of the electromagnetic induction type, when the transmitting and receiving coils are brought close to the coils having different directivities, unnecessary electromagnetic induction between the coils is generated, which causes noise. The combination with the magnetic marker (C) which is not required is preferable.

The above (A) having only one directivity
In practicing the present invention using two markers (C) to (C), the following combinations are used so that the directivity of the signal transmitted from the marker matches the directivity of the electromagnetic wave generated from the means (1). The information display (2) can be configured in combination. The information display (2) may be such that markers each having only one directivity are separately prepared as in the related art, and then they are integrated so as to have the above-described arrangement, or a shape having such an arrangement in advance. The components of the marker may be operably embedded in a single housing made as described above. In the combinations below the markers (A) to (C), the combination of the indicators shown as the indicator 6 is most preferable.

[0050]

[Table 1]

In the case where two or more markers having only one directivity are combined to form the information display (2), the information display (2) is formed by using one marker having two or more directivities. In any case, it is optimal to use the magnetic marker (C).

Here, the most preferred magnetic marker (C)
The description of the information display body using is described below.

The feature of this magnetic marker (C) is that the frequency of forming the magnetic field is gradually changed from a low frequency to a high frequency or from a high frequency to a low frequency, and the incident AC voltage is varied. For a magnetic field,
Alternatively, in a state where a magnetic pattern corresponding to a bias magnetic field is magnetized in a magnetic field generating element with respect to an alternating magnetic field of white noise having a burst frequency of all frequencies, at least one predetermined frequency at which a magnetic flux density or a magnetic permeability changes is used. The point is that it is generated and responded to as an identification signal.

Since no bias magnetic field is generated when the magnetic field generating element is not magnetized, the output signal based on a predetermined frequency at which the magnetic flux density or the magnetic permeability changes with respect to the fluctuating incident alternating magnetic field is based on the magnetostriction. It does not occur from highly magnetically permeable metals having properties.

The configuration of the magnetic marker (C) will be described with reference to FIG. 4 which is an example. A magnetic pattern corresponding to a bias magnetic field mechanically resonates with a magnetized bias magnetic field generating element 21 at a specific frequency in an incident alternating magnetic field of a fluctuating frequency to change a magnetic flux density or a magnetic permeability. The magnetically permeable metal 22 is laminated so that it can resonate mechanically.

As the bias magnetic field generating element 21, a flat hard magnetic material strip having a higher coercive force than the highly permeable metal 22 can be used. In particular,
A thin body of a ferromagnetic material such as SAE1095 steel, baicaloy, anochrome, stainless steel, nickel, ferrite, and soft iron can be used. Alternatively, a housing made of a molded product into which iron oxide-based magnetic powder such as barium ferrite is kneaded can be used.

Alternatively, the saturation magnetic flux density in the binder is 70 em
A dried coating film formed by dispersing magnetic powder of u / g or more may be used. Alternatively, even if a material other than the above is used, a material in which a bias magnetic field intensity generated when a magnetic pattern is magnetized on the bias magnetic element 21 causes magnetostriction of the highly permeable metal 22 having magnetostriction can be used. .

As the non-magnetic casing 23, any one of known and commonly used synthetic resins can be used. For example, polystyrene, polymethyl methacrylate, ABS, vinyl chloride, polyethylene, polypropylene, polycarbonate, PET, PBT, PPS, etc. Is raised.

The predetermined frequency at which the highly permeable metal 22 having magnetostriction mechanically resonates and the magnetic flux density and the magnetic permeability rapidly change is peculiar to the length of the metal. Defined

[0060]

[Equation 1] fn = n / 2L√ (D / ρ)

Where n is an integer, L is the length of the metal 22, D is the Young's modulus of the metal, and ρ is the density of the metal.

As the metal 22 which is provided with a bias magnetic field and which responds to an alternating magnetic field having a predetermined frequency among the fluctuating frequencies given from the outside, a highly permeable metal material having magnetostriction is used. Can be used, and the magnetostriction is 1
A ferromagnetic metal having a content of 5 ppm or more is preferable, and a material having the above-mentioned magnetic permeability of 100 or more is more preferable. Specifically, for example, when the maximum magnetic field strength is 0.25 Oe at 1 KHz, it is particularly preferable that the strength be 1000 or more.

Examples of such a metal 22 include an amorphous metal manufactured by Allied Signal Inc., for example, Metoglass “2605”.
SC "," 2605CO "," 2826MB ", amorphous metal" VIROVAC40 "manufactured by Vacuum Schmelz
40 "and the like.

The shape of the metal 22 is not particularly limited, and may be a deformed plate such as a trapezoid, a parallelogram, a hexagon, or the like.
There are long and narrow strips such as strips and wires.
The latter strip shape is preferred.

In order to reduce the influence of the demagnetizing field and the non-linear vibration caused by the shape, the shape is preferably rectangular.
In order to obtain the vibration direction of only the long side, it is preferable that the ratio of the long side to the short side is 15 or more.

Further, by combining metals 22 having long sides having different lengths, the capacity for marker identification is greatly improved. Incidentally, the shape of the metal shown in the figure is a strip shape. The thickness is 15 to 35 μm
It is preferred that

In actually using the marker,
As described above, a bias magnetic field is applied to the metal 22 from the magnetic field generating element 21. When the magnetic field generating element 21 is a permanent magnet that has been magnetized in advance, the magnetic field generating element 21 may be used as it is. However, when the magnetic field generating element 21 is not magnetized, for example, the magnetized magnetic pattern of the magnetic field generating element 21 may be provided at equal intervals. So that a bias magnetic field is generated. Note that it is preferable to select a bias magnetic field having an optimum intensity so that the mechanical resonance of the metal 22 becomes as large as possible.

Further, when a transmission antenna coil is provided close to the magnetic marker (C), the magnetic marker (C)
An AC magnetic field can be efficiently applied to the device. It is particularly preferable that a coil wire is directly wound around the magnetic marker (C) and the magnetic marker (C) and the transmitting antenna coil are integrated.

As an example of the information display (2),
A magnetic marker (C) wound with a coil wire for a transmitting antenna may be used. Alternatively, two or more transmission antenna coil wires are basically arranged so that the directivity of the magnetic marker (C) wound with the transmission antenna coil wire having one directivity is perpendicular to each other. One of the markers using a display in which markers wound around are combined, or two or more transmitting antenna coils having two or more directivities and their directivities being vertical. Can be used as the information display (2).

In the case where at least two magnetic markers (C) wound with the coil wire for the transmitting antenna are used, specifically, as shown in FIG. It is preferable that each of them resonate at a different frequency, and the assembling form may be any of T-shaped, cross-shaped, and L-shaped. When buried underground, one of the magnetic markers (C) is placed on the straight line. , Preferably parallel to the ground surface.

In the case of detecting the position on the ground plane, the number of magnetic markers (C) wound with the transmission antenna coil wire is as follows:
It is preferable that at least three resonances occur at different frequencies, and as a built-in form, as shown in FIG. 6, the projections of the markers 12 and 12 ′ having directivity parallel to the ground plane are T-shaped, The remaining markers 11 may be incorporated so as to be cross-shaped or L-shaped and have directivity perpendicular to the two projected markers. Projected onto the surface of the earth 2
The two markers 12 and 12 'are parallel to the surface of the earth and preferably perpendicular to each other.

When assembling the magnetic marker (C), the magnetic marker (C) may be buried in the ground so that the assembling form can be maintained. However, in order to maintain the assembling form, a known and commonly used adhesive or adhesive can be used. It may be fixed.

Examples of the adhesive include a vinyl chloride-propionic acid copolymer, a rubber-based resin, a cyanoacrylate resin, a cellulose-based resin, an ionomer resin, a polyolefin-based resin, and a polyurethane resin. Examples of the material include vinyl chloride resin, vinyl acetate resin, vinyl chloride / vinyl acetate copolymer, ethylene / vinyl acetate copolymer, vinyl chloride / propionic acid copolymer, rubber resin, acrylic copolymer resin, cyano resin Examples include acrylate resin, cellulose resin, ionomer resin, polyolefin resin, polyurethane resin, polyester resin, polyamide resin, acrylonitrile butadiene resin, natural rubber, rosin and the like.

Alternatively, a housing that can maintain the built-in form may be formed. For example, after incorporating a magnetic marker into a shallow draw forming material of a predetermined form of a known and commonly used resin film and a lid material, the sealing may be performed by impulse sealing, ultrasonic fusion, or high frequency welding.

Materials usable as the resin film include, for example, polyethylene film, polypropylene film, polyvinyl chloride film, polyvinylidene chloride film, polyethylene naphthalate film, polyvinyl alcohol film, polyethylene terephthalate (P
ET) plastic films or sheets comprising films, polycarbonate films, nylon films, polystyrene films, ethylene vinyl acetate copolymer films, ethylene vinyl copolymer films, etc .; or non-magnetic metals such as aluminum; paper, impregnated paper; A composite made of each material can be mentioned, and other materials can be used without particular limitation as long as they have the necessary strength, configuration, and the like.

Alternatively, a housing may be formed by molding into a predetermined form using a known and commonly used resin, and a magnetic marker may be incorporated. An existing plastic stake or the like can be used as the appearance of the housing. As the resin, for example, polystyrene, polymethyl methacrylate, AB
S, vinyl chloride, polyethylene, polypropylene, polycarbonate, PET, PBT, PPS and the like can be used.

According to the position detecting method of the present invention, a movable signal output recognition device capable of receiving an electromagnetic wave from the transmitting antenna coil of the means (1) and detecting a directional electromagnetic wave generated from the information display (2). The position of the information display (2) can be detected by using a known and conventional detection system including the receiving antenna coil of the means (3).

At this time, the electromagnetic wave of the display (2) has at least two directivities, the directivities are perpendicular to each other, and one of the directivities is the same as the directivity of the electromagnetic wave generated from the transmitting antenna coil. By measuring the signal output of each of the information indicators buried in the ground so as to coincide with each other, for example, the signal output in the X direction and the Y direction, the corresponding value of the ratio at a plurality of measurement positions can be obtained. The ground surface buried position corresponding to the underground buried position may be specified by the maximum value of.

The method of detecting the position of the information display (2) of the present invention is as follows, as described above. Electromagnetic wave generating means buried in the ground to generate directional electromagnetic waves (1)
An information display (2) for generating a signal having directivity embedded in the ground and responding by electromagnetic induction of electromagnetic waves from the means (1); and a signal generated from the display (2). And a movable recognizing means (3) for recognizing the signal output and detecting the signal output.
Is buried in the ground so that the directivity of the signal transmitted from the display (2) matches the directivity of the electromagnetic wave generated from the means (1), and the means (3) is horizontally moved along the surface of the ground. In the direction (3), the signal output value in the vertical direction on the ground surface at each moving position is determined by the means (3), and the ground surface buried position corresponding to the ground buried position of the information display (3) is specified. How to detect the position of underground objects.

Further, an electromagnetic wave generating means (1) buried in the ground to generate an electromagnetic wave having directivity, and said means (1)
An information display (2) for generating signals having at least two directivities buried in the ground and responding to the electromagnetic induction of electromagnetic waves from the apparatus, and detecting a signal generated from the display (2) Movably recognizing means (3) for recognizing respective signal outputs, and the information display (2) is provided with one directivity of a signal transmitted from the display (2). Buried in the ground so as to match the directivity of the electromagnetic wave generated from the ground, and by moving the means (1) and the means (3) in the horizontal direction along the surface of the ground, the means (3) (1) At each position of the movement, a signal output value in the vertical direction and the same horizontal direction on the ground surface is obtained,
An underground buried object position detecting method for identifying a surface buried position corresponding to the underground buried position of the information display (3) when the ratio of the signal output values of the respective positions becomes a maximum value.

The information display (2) is electrically resonating at a predetermined frequency in accordance with each directivity generated from the means (1). B) has a carrier or an information indicator (C)
Responds by mechanically resonating and changing the magnetic flux density and magnetic permeability.

Further, the most preferable position detecting method using the information display (2) which is the most preferable magnetic marker (C) is as follows.

An incident alternating magnetic field generating means (1 ') buried in the ground and having directivity for sweeping a frequency to generate a fluctuating frequency, and a mechanical frequency at a predetermined frequency among the frequencies generated from the means (1'). At least two different buried in the ground, where the magnetic flux density and permeability change
Movable display means (2 ') which detects a signal having a directivity and generates a signal having a certain directivity, and detects that the display (2') resonates at a predetermined frequency and recognizes each signal output. 3 ′), and the information display (2 ′) has one of the directivities of resonance frequencies transmitted from the display (2 ′) perpendicular to the ground surface and the other resonance frequency being another resonance frequency. It is buried in the ground so as to be perpendicular to the directivity, and by moving the means (3 ') horizontally along the surface of the earth, the means (3') can be moved by the means (3 '). In the position, the signal output value at which the directivity of the information display resonates at a predetermined frequency corresponding to the vertical direction and the horizontal direction on the ground surface is determined at a number of measurement positions, and the ratio of the signal output value at each position is the maximum value. Information display (2 ')
A method of detecting the position of an underground buried object that specifies the surface buried position corresponding to the underground buried position of the above.

In the correspondence between the present invention and the preferred method, the means (1) corresponds to the means (1 '), the information display (2) corresponds to the means (2'), and the recognition means (3) corresponds to the means. Same (3 ')
, Respectively.

The identification of the magnetic marker (C) including the means (1), the means (3) and the means for identifying the magnetic marker (C) resonating at a predetermined frequency as the display (2) is embodied. As the detecting device, any known and commonly used detecting device can be used in combination. For example, a suitable magnetic field generating device such as an incident AC magnetic field generating means (1 '), for example, a magnetic field generating device including a normal solenoid coil and a power supply, or the like can be used. A fluctuating alternating magnetic field is generated by the means and applied to the magnetic marker.

In the present invention, in order to improve the accuracy of detection and identification, the synchronization of the detection signal with the AC magnetic field of the means (1 ') corresponding to the electromagnetic field having directivity of the means (1) is adjusted. Good. The frequency may be varied from small to large or large to small, or may be white noise including a bursty broadband frequency.

FIG. 7 shows an example of a position detection method for specifying the underground position by using the maximum value of the ratio of the signal outputs resonating at a predetermined frequency whose directivity corresponds to the vertical direction and the horizontal direction on the ground surface.

First, the apparatus 100 is an example of an incident AC magnetic field generating means (1 '), and includes an oscillator 101 for generating a sine wave signal whose frequency can be swept, an output amplifier 102 for amplifying the sine wave signal, and An exciting coil 103 corresponding to the transmitting antenna coil of the means (1), which can apply an AC magnetic field to the metal of the magnetic marker (C) in the information display (2) with the amplified sine wave signal. .

The device 200 is an example of the recognition means (3), and detects the frequency at which the magnetic marker (C) in the information display (2) mechanically resonates. 201 and a device 202 capable of measuring the amplitude of a response signal thereof, such as a spectrum analyzer, etc., and a buried position in the ground for calculating the ratio of the signal output, that is, the amplitude of the signal output at a predetermined resonance frequency whose directivity corresponds to the vertical direction and the horizontal direction on the ground surface. And a detection device 203 of the ground surface buried position corresponding to

The magnetic field generating element of the magnetic marker (C) is magnetized using, for example, a magnetic encoder or the like, and has a predetermined magnetic pattern corresponding to a target bias magnetic field. The magnetostrictive metal inside resonates at the frequency of the expression (1) according to the magnetic pattern among the fluctuating frequencies in the incident AC magnetic field formed by the means (1 ′).

Therefore, in the vicinity of the ground surface position corresponding to the underground position where the marker (C) is buried, that is, in the detection region where the marker (C) whose magnetic pattern is magnetized is formed, the means (1 ') is formed. When the frequency of the incident alternating magnetic field is swept, a characteristic signal is generated. This is because when an alternating magnetic field and a bias magnetic field generated by a magnetic field generating element in which a magnetic pattern is magnetized are introduced into a metal exhibiting magnetostriction, energy is alternately accumulated in magnetic energy and mechanical energy according to the frequency of the alternating magnetic field. Because it is released. The stored and released magnetic energy is greatest at the material's mechanical resonance frequency.

Due to the accumulation and release of the energy, a current flows through a change in the magnetic permeability of the magnetostrictive metal, that is, a magnetic flux density, to a detection coil corresponding to, for example, a reception antenna coil, which is a component of the recognition means (3). Be guided. Therefore, the directivity of the output signal induced in the detection coil 201 is obtained by examining the amplitude of a specific frequency component corresponding to the vertical direction and the horizontal direction on the ground surface, calculating the ratio, and specifying the position of the maximum value. In addition, it is possible to specify the ground surface burying position corresponding to the underground burying position.

In the case of the device shown as an example, the electromagnetic wave (for example, the excitation frequency of the oscillator 101) generated from the transmitting antenna coil of the means (1) and the electromagnetic wave (for example, the detecting coil 20) received by the receiving antenna coil of the means (3) are used.
(1 detection band) is desirably in the range of 10 KHz to 5 MHz. The strength of the AC magnetic field generated in the exciting coil 103 is preferably 10 Oe or less, and such a magnetic field does not erase or attenuate the magnetic pattern magnetized by the bias magnetic field generating element.

According to the method of detecting the position of the ground buried position corresponding to the underground buried object of the present invention, not only can the ground surface position of the information display device be specified with extremely high accuracy, but also information on the ground surface position is provided. be able to.

The distance at which a conventional general marker, for example, a marker typified by an LC resonance circuit, is detected by an integrated antenna for transmission and reception can be read only at the level of at most several tens of centimeters, but is separated at the order of 1 m. However, since a single marker having only one directivity can be detected, the marker position is detected with an accuracy within ± several tens of centimeters and the buried position is specified.

Furthermore, the sharp different directivities must be at least 2
More than one marker with one or more directivity by keeping the information display so that they have more than one, and they are in a specific arrangement. , The embedding position is specified, and the superiority that can be detected irrespective of the noise level is shown.

Furthermore, since the signal output at a predetermined frequency whose directivity is parallel to the ground surface shows a maximum around several tens of centimeters from the ground-embedded position of the information display, the receiving coil is placed on the ground corresponding to the information display-embedded position. When approaching the position, there is an advantage that information for prompting the presence detection can be shown.

Further, since the predetermined frequency whose directivity is perpendicular to the surface of the ground can be set to two or more frequencies, the discriminating property can be given to the information display device by using a combination of these frequencies.

Also, it has a contactless transmission and reception function,
If a marker composed of a semiconductor memory element, a communication control unit and a memory control unit is installed in a direction perpendicular to the surface of the earth, information on a position requiring a considerable data capacity,
For example, latitude, longitude, address, and the like can be incorporated.

The present invention includes the following embodiments. 1. An electromagnetic wave generating means (1) buried in the ground and generating a directional electromagnetic wave, and generating a directional signal embedded in the ground and responsive to electromagnetic induction of the electromagnetic wave from the means (1) An information display (2), and a movable recognition means (3) for detecting a signal generated from the display (2) and recognizing a signal output from the information display (2). Is buried in the ground so that the directivity of the signal transmitted from the display (2) matches the directivity of the electromagnetic wave generated from the means (1), and the means (3) is horizontally moved along the surface of the ground. In the direction (3), the signal output value in the vertical direction on the ground surface at each moving position is determined by the means (3), and the ground surface buried position corresponding to the ground buried position of the information display (3) is specified. How to detect the position of underground objects.

2. The method for detecting a surface burial position corresponding to an underground buried object according to 1 above, wherein the information display (2) is one of the following. (A) LC resonance circuit marker. (B) An electromagnetic induction type marker composed of a semiconductor memory element, a communication / memory control element, and a frequency transmission / reception element and recorded with position information and the like. (C) A magnetic pattern corresponding to a bias magnetic field mechanically resonates with a magnetized bias magnetic field generating element at a specific frequency in an incident alternating magnetic field of a fluctuating frequency to change a magnetic flux density or a magnetic permeability. A marker in which a specific frequency at which a magnetic flux density or a magnetic permeability changes is generated as position information or the like, wherein the highly permeable metal is laminated so as to be able to resonate mechanically.

3. Electromagnetic wave generating means (1) for generating electromagnetic waves having at least two directivities embedded in the ground
An information display (2) for generating a signal having at least two directivities buried in the ground and responding by electromagnetic induction of electromagnetic waves from the means (1); and from the display (2). Movable recognition means (3) for detecting generated signals and recognizing respective signal outputs,
The information display (2) is buried in the ground such that the directivity of a signal transmitted from the display (2) matches the directivity of an electromagnetic wave generated from the means (1). )
Is moved in the horizontal direction along the surface of the ground, and the indicator (3) at each position of the movement is moved by the means (3).
The signal output value in the vertical direction and the same horizontal direction is obtained on the ground surface of the directivity, and the position where the ratio of the signal output value of each position becomes the maximum value corresponds to the underground position of the information display (3). A method for detecting the position of an underground object that specifies the position of the underground surface.

4. 4. The method for detecting a surface buried position corresponding to an underground buried object according to the above 3, wherein the information display (2) is one of the following. (A) LC resonance circuit marker. (B) An electromagnetic induction type marker composed of a semiconductor memory element, a communication / memory control element, and a frequency transmission / reception element and recorded with position information and the like. (C) A magnetic pattern corresponding to a bias magnetic field mechanically resonates with a magnetized bias magnetic field generating element at a specific frequency in an incident alternating magnetic field of a fluctuating frequency to change a magnetic flux density or a magnetic permeability. A marker in which a specific frequency at which a magnetic flux density or a magnetic permeability changes is generated as position information or the like, wherein the highly permeable metal is laminated so as to be able to resonate mechanically.

5. The information display (2) mechanically resonates with a bias magnetic field generating element in which a magnetic pattern corresponding to the bias magnetic field is magnetized at a specific frequency in an incident alternating magnetic field of a fluctuating frequency, and the magnetic flux density or the magnetic permeability changes. Do
A signal having at least two directivities in which a specific frequency at which a magnetic flux density or a magnetic permeability changes is generated as position information or the like, in which a highly permeable metal having a magnetostrictive property is laminated so as to resonate mechanically. 4. A method for detecting a surface buried position corresponding to an underground buried object according to the above item 3, which is a marker that generates a marker.

6. Selecting, as the information display (2), at least two of the following markers, which generate only a single directional signal, may be the same or different, and
The underground device according to claim 1, wherein each marker is an information display device configured such that the directivity of a signal transmitted from the display device (2) matches the directivity of an electromagnetic wave generated from at least two means (1). How to detect the surface burial position corresponding to the buried object. (A) LC resonance circuit marker. (B) An electromagnetic induction type marker composed of a semiconductor memory element, a communication / memory control element, and a frequency transmission / reception element and recorded with position information and the like. (C) A magnetic pattern corresponding to a bias magnetic field mechanically resonates with a magnetized bias magnetic field generating element at a specific frequency in an incident alternating magnetic field of a fluctuating frequency to change a magnetic flux density or a magnetic permeability. A marker in which a specific frequency at which a magnetic flux density or a magnetic permeability changes is generated as position information or the like, wherein the highly permeable metal is laminated so as to be able to resonate mechanically.

7. The information display (2) mechanically resonates with a bias magnetic field generating element in which a magnetic pattern corresponding to the bias magnetic field is magnetized at a specific frequency in an incident alternating magnetic field of a fluctuating frequency, and the magnetic flux density or the magnetic permeability changes. Do
Highly permeable metal with magnetostriction is laminated so that it can resonate mechanically, and a specific frequency at which the magnetic flux density or permeability changes is generated as position information etc., only a single directional signal 4. The method of detecting a surface burial position corresponding to an underground buried object according to the above item 3, wherein at least two of the markers do not occur and all of which are the same markers as described above.

[0107]

The present invention will be described in more detail with reference to the following examples.

Example 1 An Fe—Ni—Mo—B-based “Metglass 2826 MB” (manufactured by Allied Signal) having a thickness of 4 μm was used.
m, and cut into a rectangle having a length of 75 mm to form a strip of magnetostrictive metal.

Next, a non-magnetic casing 23 made of a polycarbonate material having a shape shown in FIG. 4 was prepared, and the strip of the magnetostrictive metal was stored in a groove of the non-magnetic casing.

Using a metal magnetic powder “HJ-8” (manufactured by Dowa Mining Co., Ltd.) having a coercive force of 1550 Oersted and a saturation magnetic flux density of 120 emu / g, a 50 μm thick PET having a 30 μm thick magnetic coating film was obtained. The non-magnetic support is cut out along the orientation direction into a strip having a width of 10 mm and a length of 85 mm, and the film surface is adhered so that the PET film surface having a thickness of 50 μm faces the strip of the magnetostrictive metal. Three magnetic markers in which a magnetic pattern corresponding to a bias magnetic field was not magnetized yet were formed by attaching the magnetic pattern corresponding to a bias magnetic field to a non-magnetic housing in which a strip of magnetostrictive metal was stored using an agent.

The magnetic marker generates a third harmonic, a fourth harmonic, and a fifth harmonic when receiving an excitation magnetic field.
The rectangular wave pattern was magnetized at intervals of 75 mm and 75 mm so that the magnetization of the coating magnetic layer was saturated.

An exciting coil was prepared by winding a copper wire having a diameter of 1 mm 200 times around a circular core having an inner diameter of 60 mm, and the three magnetic markers were coaxially arranged inside the exciting coil.
At a depth of m, the coil center axis was buried in the vertical direction on the ground surface.

A detection coil was prepared by winding a copper wire having a diameter of 1 mm 20 times around a circular core having an inner diameter of 160 mm.

The excitation coil and the detection coil are connected to a gain phase analyzer ("41" manufactured by HP Corporation).
94A ") through a high-speed and wide-band power amplifier and a differential amplifier, and swept an AC magnetic field at a frequency of 80 to 151 KHz to measure the resonance frequency of the embedded magnetic marker and its signal output. The result is shown in FIG. The resonance frequency and signal output of each magnetic marker were also confirmed.

Example 2 Next, using two of the three obtained in Example 1, another marker was obtained as follows. Barex (Mitsui Toatsu Co., Ltd.) with a T-shaped shallow drawing as shown in FIG.
) Tray 24 and a lid member 25 were prepared. A magnetic marker that generates fifth harmonics in vertical grooves on the surface of the tray,
A magnetic marker for generating a third harmonic was stored in a groove in a direction parallel to the surface of the tray, and the lid was covered with a lid material.

Next, as shown in FIG. 7, the ground buried position corresponding to the ground buried position is determined by the maximum value of the ratio of the signal output resonating at a predetermined frequency corresponding to the vertical direction and the horizontal direction on the ground surface. We created a position detection system that identifies

In the case of the present embodiment, 1 corresponding to the fifth harmonic
The 48 KHz signal output becomes a signal output of a predetermined frequency whose directivity is vertical to the ground surface, and corresponds to the third harmonic.
9 KHz is a signal output of a predetermined frequency whose directivity is parallel to the ground surface.

Next, the information display device prepared in this embodiment is buried so that the upper end thereof is at a depth of 1 m from the ground surface, and the information display device is located 0.8 m away from the ground burial point corresponding to the underground burying position. The signal outputs of the third harmonic and the fifth harmonic were measured. FIG. 10 shows the measurement results.

The ratio between the signal output at a predetermined frequency whose directivity is perpendicular to the ground surface and the signal output at a predetermined frequency whose directivity is parallel to the ground surface was measured. The result is shown in FIG.

From this result, in the case of this embodiment, it is possible to detect even if the information display is buried at a depth of 1 m, and furthermore, the position of the information display corresponding to the ground surface of the buried object is ± 10%.
It can be seen that detection is performed with an accuracy within a centimeter.

[0121]

According to the first aspect of the present invention, the electromagnetic wave generating means for generating electromagnetic waves having directivity is buried in the ground together with the information display, so that a conventional general information display, for example,
Compared to the distance at which the marker represented by the LC resonance circuit is detected by the integrated transmitting and receiving antenna, reading can be performed even if the display is farther (or deeper) from the receiving antenna, and detection can be performed more sufficiently. (The detection area is enlarged.) The information display position is detected with higher accuracy than in the past, and the ground position with a small error is specified. The same applies to the case where only one information display that generates a signal having only one directivity is used.

According to the second aspect of the present invention, at least one of the information displays for generating signals having at least two directivities is used instead of only one of the information displays for generating signals having only one directivity. Or a plurality of information display devices that generate a signal having only one directivity are used at a specific position, so that a ground position with higher accuracy and a smaller error can be specified than in claim 1. . It is also less affected by noise levels.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a diagram showing a state in which an information display device having a single directivity is buried in the ground so as to have directivity vertically and a receiving antenna coil moves parallel to the ground (thick dotted arrow). FIG. 2 is a schematic explanatory view showing the basic concept of FIG.

FIG. 2 shows a state in which an information display device having a single directivity is embedded with directivity parallel to the ground, and a receiving coil moves parallel to the ground (thick dotted arrow). FIG. 2 is a schematic explanatory diagram showing a basic concept.

FIG. 3 shows an information display in which two types of directivities of an information display are arranged such that one directivity is vertical to the ground (directivity X) and the other directivity is parallel to the ground (directivity Y). FIG. 3 is a schematic explanatory view showing a basic concept of the present invention showing a state in which a receiver is buried and a receiving coil moves parallel to the ground.

FIG. 4 is a diagram illustrating an example of a configuration of a magnetic marker (C).

FIG. 5 is a diagram showing an example of creating an information display in the case of detecting a position on a straight line on the ground surface.

FIG. 6 is a diagram showing an example of creating an information display device in the case of detecting a position on a plane on the ground surface.

FIG. 7 is a schematic explanatory view showing an example of a position detection method for specifying an underground buried position based on a maximum value of a ratio of signal outputs resonating at a predetermined frequency corresponding to a vertical direction and a horizontal direction on the surface of the ground.

FIG. 8 is a diagram showing a result of measuring a resonance frequency of a magnetic marker (C) whose directivity is perpendicular to the ground surface and a signal output thereof in the example.

FIG. 9 shows a T-shaped shallow aperture of 250 μm created in the example.
FIG. 3 is a configuration diagram of a tray and a cover material of a thick barex (manufactured by Mitsui Toatsu Co., Ltd.).

FIG. 10 is a view showing a result of measuring a signal output of a predetermined frequency whose directivity is vertical and parallel to the ground surface.

FIG. 11 is a diagram showing a result of measuring a ratio between a signal output of a predetermined frequency whose directivity is perpendicular to the ground surface and a signal output of a predetermined frequency whose directivity is parallel to the ground surface.

[Explanation of symbols]

Reference Signs List 1 Information display 2 Ground surface 3 Transmitting antenna coil 4 Signal recognizing means excluding transmitting antenna coil (3) [Oscillator for generating electromagnetic wave, power supply, etc.] X Directivity of information display indicates vertical state on the ground. Y Indicates a state where the directivity of the information display is parallel to the ground. 5 Magnetic flux lines perpendicular to the ground surface generated from the information display 5 'Magnetic flux lines parallel to the ground generated from the information display 6 Receiving antenna coil 11 Directivity X information display 12 Directivity Y information display 12' Direction Directional information display perpendicular to directivity X and directivity Y 21 Bias magnetic field generating element 22 Highly permeable metal having magnetostrictive property 23 Non-magnetic housing 24 Tray 25 Cover material 100 Electromagnetic wave generating means (1 except transmitting antenna coil) ) [Example of device of incident AC magnetic field generating means (1 ')] 101 Oscillator for generating sine wave signal 102 Output amplifier 103 Transmitting antenna coil (exciting coil) 200 Signal recognition means excluding receiving antenna coil (3)
[Example of device of detecting means (3 ')] 201 Receiving antenna coil (detection coil) 202 Device capable of detecting resonance frequency and measuring amplitude of response signal 203 Device for detecting surface buried position

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Tatsunori Sada 2-4-7-204, Shimizuguchi, Shirai-machi, Inba-gun, Chiba Prefecture (72) Inventor Shige Tonaki 1434-2 Matsudo, Matsudo-shi, Chiba Sun Heights B IGI 302

Claims (7)

[Claims] An electromagnetic wave generating means (1) buried in the ground to generate an electromagnetic wave having directivity, and a directional buried in the ground responsive to electromagnetic induction of electromagnetic waves from the means (1). Information display (2) for generating a signal having
And a movable recognizing means (3) for detecting a signal generated from the display (2) and recognizing the signal output. The information display (2) is provided with the information display (2). ) Is buried in the ground such that the directivity of the signal transmitted from the means (1) matches the directivity of the electromagnetic wave generated from the means (1), and the means (3) is moved horizontally along the surface of the ground, The position of an underground buried object that determines a signal output value in the vertical direction on the surface of the ground at each moving position by the means (3) and specifies a surface buried position corresponding to the underground buried position of the information display (3). Detection method. 2. The method according to claim 1, wherein the information display is one of the following: (A) LC resonance circuit marker. (B) An electromagnetic induction type marker composed of a semiconductor memory element, a communication / memory control element, and a frequency transmission / reception element and recorded with position information and the like. (C) A magnetic pattern corresponding to a bias magnetic field mechanically resonates with a magnetized bias magnetic field generating element at a specific frequency in an incident alternating magnetic field of a fluctuating frequency to change a magnetic flux density or a magnetic permeability. A marker in which a specific frequency at which a magnetic flux density or a magnetic permeability changes is generated as position information or the like, wherein the highly permeable metal is laminated so as to be able to resonate mechanically. 3. An electromagnetic wave generating means (1) for generating electromagnetic waves having at least two directivities embedded in the ground,
An information display (2) for generating a signal buried in the ground and having at least two directivities, which responds by electromagnetic induction of electromagnetic waves from the means (1); and an information display (2) generated from the display (2). Movable recognition means (3) for detecting signals and recognizing respective signal outputs,
The information display (2) is buried in the ground such that the directivity of a signal transmitted from the display (2) matches the directivity of an electromagnetic wave generated from the means (1). )
Is moved in the horizontal direction along the surface of the ground, and the indicator (3) at each position of the movement is moved by the means (3).
The signal output value in the vertical direction and the same horizontal direction is obtained on the ground surface of the directivity, and the position where the ratio of the signal output value of each position becomes the maximum value corresponds to the underground position of the information display (3). A method for detecting the position of an underground object that specifies the position of the underground surface. 4. The method according to claim 3, wherein the information display is one of the following: (A) LC resonance circuit marker. (B) An electromagnetic induction type marker composed of a semiconductor memory element, a communication / memory control element, and a frequency transmission / reception element and recorded with position information and the like. (C) A magnetic pattern corresponding to a bias magnetic field mechanically resonates with a magnetized bias magnetic field generating element at a specific frequency in an incident alternating magnetic field of a fluctuating frequency to change a magnetic flux density or a magnetic permeability. A marker in which a specific frequency at which a magnetic flux density or a magnetic permeability changes is generated as position information or the like, wherein the highly permeable metal is laminated so as to be able to resonate mechanically. 5. An information display (2) mechanically resonates at a specific frequency in an incident alternating magnetic field of a variable frequency with a bias magnetic field generating element in which a magnetic pattern corresponding to a bias magnetic field is magnetized, and Or the permeability is changed, high permeability metal having magnetostriction is laminated so that it can be mechanically resonated, a specific frequency at which the magnetic flux density or permeability changes is generated as position information or the like, at least 2
4. The method for detecting a surface buried position corresponding to an underground buried object according to claim 3, wherein the marker generates a signal having two directivities. 6. The information display (2), which generates only a single directional signal, may be the same or different,
At least two of the following markers are selected, and each marker is selected such that the directivity of a signal transmitted from the display (2) matches the directivity of an electromagnetic wave generated from at least two means (1). The method for detecting a surface buried position corresponding to an underground buried object according to claim 1, wherein the information display device is constituted. (A) LC resonance circuit marker. (B) An electromagnetic induction type marker composed of a semiconductor memory element, a communication / memory control element, and a frequency transmission / reception element and recorded with position information and the like. (C) A magnetic pattern corresponding to a bias magnetic field mechanically resonates with a magnetized bias magnetic field generating element at a specific frequency in an incident alternating magnetic field of a fluctuating frequency to change a magnetic flux density or a magnetic permeability. A marker in which a specific frequency at which a magnetic flux density or a magnetic permeability changes is generated as position information or the like, wherein the highly permeable metal is laminated so as to be able to resonate mechanically. 7. An information display (2) mechanically resonates at a specific frequency in an incident alternating magnetic field of a variable frequency with a bias magnetic field generating element in which a magnetic pattern corresponding to a bias magnetic field is magnetized, and Alternatively, a specific frequency at which the magnetic permeability changes or a magnetic flux density or a magnetic permeability changes, which is laminated so that a highly permeable metal having magnetostriction can be mechanically resonated, is generated as position information or the like. 4. The method of detecting a ground buried position corresponding to an underground buried object according to claim 3, wherein at least two of all the same markers that generate only one directional signal are generated.