JP2000009400A - Method and element for detecting misfired crushing powder or explosive - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect crushing powder or explosive accurately regardless of the conductivity or permittivity of an object to be blasted, e.g. rock, bed rock or concrete, even if an electromagnetic wave reflecting material, e.g. iron rod, is mixed. SOLUTION: A detecting element 10 comprising an antenna coil 11 and a capacitor 13 connected across the antenna coil 11 to form a resonance circuit 12 along with the antenna coil 11 is set at a specified place along with a crushing powder or explosive 15. After the crushing powder or explosive 15 is combusted, a radio wave having resonance frequency of the resonance circuit 12 is transmitted to the specified place and the detecting element 10 is detected based on the presence of reflected radio wave from the antenna coil 11 thus detecting misfired crushing powder or detonator 15.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for crushing or exploding a crushed or explosive loaded in a predetermined place in order to crush or blast rock, bedrock, concrete or the like. The present invention relates to a detection method for detection and a detection element thereof.

[0002]

2. Description of the Related Art A hole is formed in rock, bedrock, concrete, or the like, and a columnar crushing agent or explosive is loaded therein, the upper portion of the hole is sealed with wet sand, etc., and the crushing agent or explosive is burned. Methods of blasting rocks, bedrock, concrete, and the like with leverage or explosives are well known. Generally, after blasting a crushing agent or explosive, it is necessary to remove shear such as earth and sand and rocks. However, if the shear is removed with a shovel or the like without noticing the presence of the unexploded crushed or explosive, the unexploded crushed or explosive explodes due to some impact, causing serious problems in safety management. Heretofore, a method for detecting or detecting this type of unexploded and remaining crushed or explosive has been proposed (JP-A-5-312500,
JP-A-8-61900). The former JP-A-5-31250
In the method for detecting residual explosives disclosed in Japanese Patent Publication No. 0, an electromagnetic wave reflecting material such as aluminum foil is wrapped around an explosive and fixed, and the explosive is loaded into a plurality of charging holes, blasted, and then unexploded. A transmission / reception antenna is used to transmit / receive a detection radio wave to an area where the explosive body may exist. If an unexploded explosive is present at this time, a reflected wave that can be reliably detected from the aluminum foil provided around the explosive without being affected by the surrounding conditions, such as rock, will be used to detect the presence of the unexploded explosive. It can be detected accurately. Further, in the latter method for detecting residual medicine shown in Japanese Patent Application Laid-Open No. 8-61900,
In the explosive or non-explosive composition buried in the crushing point, the tip of the residual explosive detector made of a high-strength wire is inserted in advance, and after the burning operation on the explosive or non-explosive composition is completed, the residual When the medicine detector is pulled out and the state of the tip of the residual medicine detector does not change, it is determined that the explosive or the non-explosive composition exists at the crushed portion.

[0003]

However, according to the former detection method (Japanese Patent Laid-Open No. Hei 5-312500), the rock, bedrock, concrete or the like to be blasted already contains an electromagnetic wave reflecting material such as a reinforcing bar, a coin, or aluminum foil. In such a case, the transmitted electromagnetic wave also reacts to these reinforcing bars and the like, so that unexploded explosives cannot be accurately detected. In this detection method, it is necessary to use radio waves of a high frequency of about 1 GHz in order to effectively reflect electromagnetic waves with an electromagnetic reflection material. However, high frequency radio waves are objects of low conductivity and low dielectric constant. Only penetrates. For this reason, blastable materials such as rock, bedrock, and concrete suitable for the above detection method are limited to those having low conductivity and a small dielectric constant. If the characteristics of these blastable materials are not known, high-precision detection is performed. Cannot be guaranteed. In the latter detection method (Japanese Unexamined Patent Publication No. 8-61900), it is necessary to visually find and remove the residual explosive detector after the completion of the burning operation on the explosive or non-explosive composition. There was a problem that the location of the residual medicine detector after blasting might be unknown depending on the state of the burial place and the blasting state. It is an object of the present invention to accurately determine whether the material to be blasted such as rock, bedrock, concrete or the like has an electric conductivity or a dielectric constant, and even if these materials to be blasted are mixed with an electromagnetic reflecting material such as a reinforcing bar. An object of the present invention is to provide a method capable of detecting an unexploded crushed explosive or explosive and a detection element thereof.

[0004]

The invention according to claim 1 is
As shown in FIG. 1, a detection element 10 having an antenna coil 11 and a capacitor 13 connected to both ends of the antenna coil and forming a resonance circuit 12 with the antenna coil.
Is installed in a predetermined place together with the crushing agent or the explosive 15 and the burning operation of the crushing agent or the explosive 15 is performed.
Transmitting a radio wave having a resonance frequency to the predetermined location,
In this method, the detection element 10 is detected based on the presence of a radio wave reflected from the antenna coil 11 to detect unexploded and remaining crushed powder or explosive 15. If the crushing agent or explosive 15 is blasted by the burning operation, the resonance circuit 12 is also destroyed at the same time as the blasting, so that even if a radio wave having the resonance frequency of the resonance circuit is transmitted, there is no reflected radio wave, and the unexploded crushing agent or It can be seen that the explosive 15 does not remain. Conversely, if a reflected radio wave is detected, it is understood that unexploded crushed powder or explosive 15 remains.

[0005] The invention according to claim 2 is an antenna coil 1
1 and a capacitor 13 connected to both ends of the antenna coil and forming a resonance circuit 12 with the antenna coil 11
And a detection element comprising: When the antenna coil 11 receives a primary radio wave of a predetermined frequency from the detection device, the resonance circuit 12 of the detection element resonates, and transmits a secondary reflected radio wave from the antenna coil 11 to the detection device.

A third aspect of the present invention is the detection element according to the second aspect, wherein the antenna coil 11 is disposed so as to wind around a columnar crushing agent or explosive 15. By arranging the antenna coil 11 around the crushing agent or the explosive 15, the detecting element is easily broken when the crushing agent or the explosive blasts.

The invention according to claim 4 is the invention according to claim 3, which is disposed between the antenna coil 11 and the columnar crushing agent or explosive 15 so as to wind around the crushing agent or explosive 15. This is a detection element having a thin-film or thin-plate magnetic material 14. By interposing the magnetic material 14, even if the number of turns of the antenna coil 11 is reduced, the resonance characteristics do not deteriorate, and even if the crushing agent or the explosive 15 is made of metal, the line of magnetic force at resonance is magnetic. Since it passes through the member 14, the self-inductance of the antenna coil 11 does not change and the resonance characteristics of the detection element do not change.

The invention according to claim 5 is the invention according to claim 4, wherein the magnetic material 14 is a detection element made of a soft magnetic metal. By making the magnetic material 14 a soft magnetic metal, the number of turns of the antenna coil 11 can be further reduced without changing the resonance characteristics of the detection element, and the self-inductance of the antenna coil 11 is not further changed, and the resonance characteristics of the detection element are improved. No change.

According to a sixth aspect of the present invention, there is provided an antenna coil 11 wound with a diameter equal to or less than the diameter of a columnar crushing or explosive charge 15, and a resonance circuit 12 connected to both ends of the antenna coil together with the antenna coil 11. And a detection element arranged near the one end of the crushing agent or explosive 15 such that the axis of the crushing agent or explosive matches the axis of the antenna coil 11. By arranging the axis of the crushing agent or explosive and the axis of the antenna coil near one end of the columnar crushing agent or explosive 15 so as to coincide with the axis of the antenna coil, the diameter of the perforation is particularly increased for the arrangement of the detecting element. Instead, the detection element can be loaded into the perforation.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The detecting element of the present invention is used for a crushing agent having no detonation or an explosive having a detonation such as dynamite. Examples of the crushing agent include black powder, propellant, concrete crushing agent, thermite composition which is a non-explosive, a crushing agent using the pressure of pyrolysis gas (trade name: Gansaiza, manufactured by Nippon Koki Co., Ltd.) High-temperature high-speed reaction compositions. As shown in FIGS. 1 to 4, the detection element 10 includes an antenna coil 11 and a capacitor 13 connected to both ends of the antenna coil and forming a resonance circuit 12 with the antenna coil. The detection element 10 is shown in FIG.
As shown in FIG. 2A, FIG. 4 and FIG. 5, whether the crushing agent or the explosive 15 is integrally attached to the columnar crushing agent or the explosive 15 and is loaded together with the crushing agent or the explosive into the perforation 16 provided at a predetermined place. Alternatively, as shown in FIGS. 1 (b) and 2 (b), without being integrated with the explosive or crushing agent 15, it is disposed in the vicinity of the explosive or crushing agent 15 in a perforation 16 provided at a predetermined place. It is then loaded with the crushing or explosive 15. After loading,
The perforations 16 are closed by a stemming material 17 such as sand. The crushing agent or explosive and the detection element of the present invention can be installed without perforation as long as they can be inserted and fixed in a gap between blastable bodies such as rock, bedrock and concrete.

FIGS. 1 (a) and 2 (a) show a method of integrally attaching the detecting element 10 to the crushing or explosive charge 15.
As shown in the figure, a method of mounting a detection element 10 having an antenna coil 11 and capacitors 13 connected to both ends of the coil so that the antenna coil 11 is wound around a cylindrical crushing or explosive 15 or As shown in FIGS. 4 and 5, a detection element 10 is formed by enclosing a resonance circuit 12 in which both ends of an antenna coil 11 are connected by a capacitor 13 with an insulating member 18, and this detection element 10 is crushed or explosive 15. After contacting the outer peripheral surface of the crushing agent or explosive 15, the adhesive tape 19 is integrated therewith. The former method shown in FIG. 1A, in which the diameter of the perforation does not need to be particularly increased for the detection element, is preferable to the latter method shown in FIG. As shown in FIGS. 4 and 5, when the detection element 10 is mounted perpendicular to the axis Y so that the axis direction X of the antenna coil 11 is parallel to the crushing agent or the explosive 15 in the axis direction Y. Compared with, the more concentrated lines of magnetic force (magnetic flux) arrive at the detection device, so that the unexploded crushing agent or explosive 15 can be detected with higher accuracy.
In FIG. 5, broken arrows indicate lines of magnetic force radiated at the time of resonance. In the mounting method shown in FIG.
1 is wound around the magnetic core 11a. The magnetic core 11a is preferably made of a soft magnetic metal. The insulating member 18 is preferably made of plastic such as polypropylene, nylon, polyester, vinyl chloride, vinyl acetate, ABS, polyethylene, epoxy resin, etc., which can be easily processed and mass-produced. The magnetic core, the antenna coil, the capacitor, and the like may be sealed in a plastic case, or may be a plastic body injection-molded so as to be cast.

As shown in FIG. 2A, when the exterior material 15a of the crushing agent or explosive 15 is made of metal, the exterior material 15a changes the self-inductance of the resonance circuit of the detection element 10 and changes the inductance. It is necessary to provide the antenna coil 11 and the capacitor 13 after providing the magnetic material 14 as a magnetic core around the exterior material 15a so that the resonance frequency does not change. Further, even if the exterior material 15a is not made of metal, the number of turns of the antenna coil 11 can be reduced by providing the magnetic material 14 so that magnetic lines of force similar to those without the magnetic material can be generated at the time of resonance. When the magnetic material 14 is provided, the antenna coil 11 is wound after an insulating paper such as Kent paper or an insulating thin film is wound on the magnetic material 14. It is preferable that the antenna coil 11 and the capacitor 13 are covered with the insulating cylinder 10a, and that the magnetic material 14 is made of a soft magnetic metal having high magnetic permeability. It is also preferable to use a thin or thin magnetic material because the magnetic material is easily destroyed when the crushing agent or explosive is blasted. In order to generate strong lines of magnetic force at resonance, a laminated body in which a plurality of thin films or thin sheets of soft magnetic metal and an insulating thin film are alternately laminated, or a plurality of thin films or thin sheets of soft magnetic metal whose surfaces are insulated are laminated. A laminated body is preferred. The soft magnetic metal thin film is a film having a thickness of 5 to 250 μm formed of iron-based amorphous, cobalt-based amorphous, permalloy or silicon steel, and the insulating thin film is a polyester film, polyvinylidene chloride, polyvinyl chloride, polyethylene terephthalate ( Thickness 5 such as PET)
It is an insulating resin film of about 50 μm. Further, the insulating thin film may be insulating paper.

As a method of not attaching the detecting element 10 integrally to the crushing agent or the explosive 15, FIGS.
As shown in FIG. 2B, a detecting element 10 having an antenna coil 11 and capacitors 13 connected to both ends of the coil is used for a crushing or explosive 1 in which the antenna coil 11 has a cylindrical shape.
There is a method in which the axis of the crushing agent or the explosive is aligned with the axis of the antenna coil at one end of 5. In this case, it is preferable that the diameter of the antenna coil 11 be equal to or smaller than the diameter of the columnar crushing agent or explosive 15 because it is not necessary to particularly increase the diameter of the perforation for the detection element. The antenna coil 11 is wound around an insulating small cylinder 10b, and after connecting capacitors 13 to both ends of the coil, the insulating large cylinder 10c is put on the small cylinder 10a and sealed with a ring-shaped lid 10d. It is preferable to keep it. It is preferable that the small cylinder 10b, the large cylinder 10c, and the lid 10d, as well as the cylinder 10a described above, be formed of plastic. The antenna coil 11 of the present invention is made of copper, copper alloy (Cu-Cr, Cu-Be, Cu-Zn) having excellent conductivity,
The conductor is made of aluminum or the like. Preferably, the conductor is covered with an insulating film. As capacitors connected to both ends of the antenna coil and forming a resonance circuit together with the antenna coil, chip capacitors, ceramic capacitors, paper capacitors, electrolytic capacitors, and the like are used.

FIG. 3 shows an equivalent circuit of the detecting element and a configuration diagram of the detecting device. The detection element shown in FIG. 3A is an equivalent circuit having no magnetic material, and the detection element shown in FIG. 1 and 3
As shown in the figure, the detection device 20 is of a stand type, and has an air-core loop antenna 21 facing the ground, a pole 22,
There is provided a gripper 24 having a detection circuit 23 built therein. The detection circuit 23 includes a transmission / reception switch 28 for a transmission unit 25, a reception unit 26, a detection display unit 27, and a control unit 29 for controlling these switches. The antenna 21 and the switch 28 are connected by a transmission line 30 passing through the inside of the pole 22. To detect the detection element 10 by the detection device 20, the detection device 20 transmits a radio wave having a resonance frequency of a resonance circuit 12 formed by the antenna coil 11 and the capacitor 13. Specifically, after the switch 28 is switched to the position shown by the solid line in FIG. 3, the radio wave of the predetermined frequency is transmitted from the antenna 21 from the transmission unit 25 under the control of the control unit 29. After the transmission, when the switch 28 is switched to the position shown by the broken line in FIG. 3, the reflected radio wave resonated by the resonance circuit 12 is received by the antenna 21 and processed by the reception unit 26 to detect that the detection element 10 is present. Display 27
Will be displayed. If the crushing agent or explosive 15 is burned successfully and the crushing agent or explosive 15 is successfully crushed, the detecting element 1
0 is destroyed, and even if the detection device 20 transmits a radio wave of a resonance frequency, no reflected radio wave is generated, and it can be seen that there is no unexploded crushing agent or explosive. If unexploded explosives or explosives remain, it is possible to easily detect the explosives or explosives by detecting the detection element by the arrival of the reflected radio wave.

[0015]

Next, embodiments of the present invention will be described. <Example 1> A magnetic material prepared by applying an acrylic paint to the surface of a soft magnetic amorphous foil (manufactured by Allied Chemical Co., trade name: METAGLAS2605S-2) having a thickness of 25 µm and a width of 50 mm to form an insulating film. did. 0.15 thickness
25mm outside diameter covered with aluminum foil
A soft magnetic amorphous foil on which an insulating film is formed is wound around a crushing agent having a length of 100 mm over a length of 2400 mm, the magnetic material is covered with a 0.3 mm thick Kent paper, and the Kent paper is further covered with an insulating film. Thickness 0.2
After forming an antenna coil by winding a copper wire of 420 mm 420 times, a chip capacitor of 230 pF was connected to both ends of the coil to produce a detection element. On the other hand, a hole having an inner diameter of 40 mm and a depth of 1000 mm was provided in the concrete mass.
After loading the crushing agent attached with the detection element at the deepest part of this perforation, a radio wave of a specific frequency is transmitted from the detection device at a place about 1000 mm away from the crushing agent, and whether or not a reflected radio wave that resonates arrives Upon examination, the detecting device detected a reflected radio wave that resonated. Next, after performing a burning operation on the crushed drug, a radio wave of a specific frequency is transmitted from the detection device in the same manner as described above, and it is checked whether or not a resonated reflected radio wave arrives. Could not be detected.

<Example 2> A crushing agent having an outer diameter of 55 mm and a length of 230 mm covered with a 0.6 mm thick cardboard was wound 770 times with a 0.3 mm thick copper wire covered with an insulating film. After forming the antenna coil, two ends
A detection element was produced by connecting a chip capacitor of 30 pF. On the other hand, the concrete block has an inner diameter of 65 mm and a depth of 1 mm.
A 200 mm perforation was provided. After loading the crushing agent attached with the detection element at the deepest part of this perforation, a radio wave of a specific frequency is transmitted from the detection device at a place about 1000 mm away from the crushing agent, and whether or not a reflected radio wave that resonates arrives Upon examination, the detecting device detected a reflected radio wave that resonated. Next, after performing a burning operation on the crushed drug, a radio wave of a specific frequency is transmitted from the detection device in the same manner as described above, and it is checked whether or not a resonated reflected radio wave arrives. Could not be detected.

[0017]

As described above, when a radio wave reflecting material such as a reinforcing bar is mixed in an object to be blasted such as rock, bedrock or concrete, or when the electric conductivity or dielectric constant of the object to be blasted is unknown. In addition, what could not be accurately detected by the conventional detection method, according to the present invention, regardless of the value of the conductivity or dielectric constant of the blasting object such as rock, rock, concrete, and the like, Even if an electromagnetic reflecting material such as a reinforcing bar is mixed, a misfired explosive or explosive can be accurately detected. In addition, since there is no visual inspection, there is an advantage that unexploded crushed explosives or explosives can be detected even when the buried state of the crushed explosives or explosives changes due to blasting or even at night.

[Brief description of the drawings]

FIG. 1 is a diagram showing a detection state of a crushed or explosive with a detection element installed at a predetermined place according to the present invention.

FIG. 2 is an enlarged perspective view of a crushed or explosive with a detection element.

FIG. 3 is a diagram showing an equivalent circuit of a crushed or explosive with a detection element and a configuration of a detection circuit of a detection device.

FIG. 4 is a side view showing how the detection element of the present invention is attached to another crushing agent or explosive.

FIG. 5 is a perspective view showing an attachment state of FIG. 4;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Detection element 11 Antenna coil 12 Resonant circuit 13 Capacitor 14 Magnetic material (magnetic core) 15 Crushed or explosive 20 Detecting device

Continued on the front page (72) Inventor Tohru Ichimura 1-5-1, Otemachi, Chiyoda-ku, Tokyo Mitsui Materials Co., Ltd. Planning Development Department (72) Inventor Seiro Yawata 1-chome Otemachi, Chiyoda-ku, Tokyo No.6-1 Intellectual Property Service Co., Ltd.

Claims (6)

[Claims] 1. A detecting element (10) comprising an antenna coil (11) and a capacitor (13) connected to both ends of the antenna coil and forming a resonance circuit (12) with the antenna coil.
Is placed in a predetermined place together with a crushing agent or explosive (15), and after performing the burning operation of the crushing agent or explosive (15), a radio wave having a resonance frequency of the resonance circuit (12) is transmitted to the predetermined place. A method of transmitting and detecting the detecting element (10) based on the presence of a reflected radio wave from the antenna coil (11) to detect unexploded and remaining crushed or explosive. 2. An element for detecting unexploded or remaining explosives comprising an antenna coil (11) and a capacitor (13) connected to both ends of the antenna coil and forming a resonance circuit (12) with the antenna coil. . 3. The element for detecting unexploded or remaining explosives or explosives according to claim 2, wherein the antenna coil (11) is arranged so as to wind around the columnar or explosives (15). 4. A thin-film or thin-plate-like magnetic material disposed between an antenna coil (11) and a columnar crushing agent or explosive (15) so as to wind around the crushing agent or explosive (15). 4. The element for detecting unexploded or remaining explosives or explosives according to claim 3, which has 14). 5. The element for detecting unexploded or remaining crushed or explosive material according to claim 4, wherein the magnetic material is made of a soft magnetic metal. 6. An antenna coil (11) wound with a diameter equal to or less than the diameter of a cylindrical crushing or explosive (15), and a resonance circuit (12) connected to both ends of the antenna coil together with the antenna coil. And a capacitor (13) that forms an explosive that is arranged near one end of the crushing agent or explosive (15) so that the axis of the crushing agent or explosive matches the axis of the antenna coil (11). For detecting crushed or explosives remaining at