JPH0862340A - Metal detecting device - Google Patents
Metal detecting deviceInfo
- Publication number
- JPH0862340A JPH0862340A JP22079294A JP22079294A JPH0862340A JP H0862340 A JPH0862340 A JP H0862340A JP 22079294 A JP22079294 A JP 22079294A JP 22079294 A JP22079294 A JP 22079294A JP H0862340 A JPH0862340 A JP H0862340A
- Authority
- JP
- Japan
- Prior art keywords
- coil
- metal
- thermal image
- magnetic field
- detected
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 239000002184 metal Substances 0.000 title claims abstract description 53
- 229910052751 metal Inorganic materials 0.000 title claims abstract description 53
- 238000001514 detection method Methods 0.000 claims abstract description 39
- 230000005291 magnetic effect Effects 0.000 claims abstract description 23
- 230000005284 excitation Effects 0.000 claims description 12
- 238000012544 monitoring process Methods 0.000 abstract description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 6
- 238000000034 method Methods 0.000 description 5
- 229910052742 iron Inorganic materials 0.000 description 3
- 230000005389 magnetism Effects 0.000 description 3
- 230000010355 oscillation Effects 0.000 description 3
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 150000002739 metals Chemical class 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 239000003302 ferromagnetic material Substances 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 230000001678 irradiating effect Effects 0.000 description 1
- 229910052759 nickel Inorganic materials 0.000 description 1
- 229910052755 nonmetal Inorganic materials 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 229910052724 xenon Inorganic materials 0.000 description 1
- FHNFHKCVQCLJFQ-UHFFFAOYSA-N xenon atom Chemical compound [Xe] FHNFHKCVQCLJFQ-UHFFFAOYSA-N 0.000 description 1
Landscapes
- Radiation Pyrometers (AREA)
- Geophysics And Detection Of Objects (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、例えば、銃や刀剣類等
の金属物体等を検知する金属検知装置に関し、特に、画
像にて金属物体等の形状を表示し得る装置に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a metal detection device for detecting metal objects such as guns and swords, and more particularly to a device capable of displaying the shape of a metal object or the like in an image.
【０００２】[0002]
【従来の技術】例えば、空港の手荷物検査装置で代表さ
れるように、出入口において、例えば、銃や刀剣類等の
凶器の存在を監視することは、社会安全上有効である。
かかるセキュリティ分野において、使用される金属物体
の検知方法として、従来、例えば、（１）Ｘ線を利用し
たもの、（２）高周波発振を利用したもの、（３）磁気
を利用したものが知られている。2. Description of the Related Art For example, as represented by a baggage inspection device at an airport, it is effective in terms of social safety to monitor the presence of weapons such as guns and swords at the doorway.
In the security field, as a method of detecting a metal object used, conventionally, there are known, for example, (1) a method using X-rays, (2) a method using high-frequency oscillation, and (3) a method using magnetism. ing.
【０００３】（１）の検知方法は、Ｘ線管とＸ線センサ
を使用したもので、Ｘ線管から物体に照射して通過して
きたＸ線の強弱分布によってＸ線センサのキセノンガス
の電離の度合いが場所により異なるのを、Ｘ線センサの
電極で検知するものである。Ｘ線の照射強度を調節する
ことにより、Ｘ線が被検知物を遮蔽する遮蔽物を透過
し、殆どの金属物体を顕在化して検知できる。（２）の
検知方法は、コイルに金属物体が近づくと、誘導電流が
生じて、コイルのインダクタンスが変化するので、発振
回路によって金属物体を検知できるものである。（３）
の検知方法は、磁気を検知する素子（ホール素子、磁気
抵抗素子、磁気ダイオード等）からなる磁気センサを用
いたもので、鉄、ニッケル等の強磁性体からなる物体を
検知するものである。The detection method (1) uses an X-ray tube and an X-ray sensor, and the xenon gas of the X-ray sensor is ionized by the intensity distribution of X-rays that pass through the X-ray tube after irradiating an object. It is detected by the electrodes of the X-ray sensor that the degree of is different depending on the place. By adjusting the irradiation intensity of the X-rays, the X-rays pass through the shield that shields the object to be detected, and most metal objects can be exposed and detected. In the detection method of (2), when a metal object approaches the coil, an induced current is generated and the inductance of the coil changes, so the metal object can be detected by the oscillation circuit. (3)
The detection method of (1) uses a magnetic sensor including an element that detects magnetism (Hall element, magnetoresistive element, magnetic diode, etc.), and detects an object made of a ferromagnetic material such as iron or nickel.
【０００４】[0004]
【発明が解決しようとする課題】しかしながら、このよ
うな従来の金属検知装置にあっては、夫々次のような問
題点がある。即ち、Ｘ線を利用したものにあっては、上
述したように検知物体の形状を識別できる点で有効であ
るが、装置が複雑かつ大掛かりであって、その取り扱い
に著しい制限があり、又、装置として高価でもある。However, each of the conventional metal detectors described above has the following problems. That is, the X-ray utilizing method is effective in that the shape of the sensing object can be identified as described above, but the apparatus is complicated and large-scale, and its handling is extremely limited. It is also expensive as a device.
【０００５】高周波発振を利用したものにあっては、装
置として安価であるが、検知物体の形状は識別できな
い。A device utilizing high-frequency oscillation is inexpensive as an apparatus, but the shape of the sensing object cannot be identified.
【０００６】磁気を利用したものにあっては、装置とし
て安価であるが、上述したように金属であっても、磁性
体のみの検知しかできず、又、検知物体の形状は識別で
きない。A device utilizing magnetism is inexpensive as a device, but as described above, even with a metal, only the magnetic substance can be detected, and the shape of the detected object cannot be identified.
【０００７】本発明は上述のような従来の問題点に鑑
み、装置の取り扱いに制限がなく、又、装置として安価
でありながら、金属物体等の形状を含んだ検知が可能で
あり、特に、セキュリティ分野において、銃や刀剣類等
の凶器の存在を監視するのに有効な金属検知装置を提供
することを目的とする。In view of the above-mentioned conventional problems, the present invention does not limit the handling of the apparatus and is inexpensive as the apparatus, but can detect the shape including the shape of a metal object. An object of the present invention is to provide a metal detection device effective for monitoring the presence of a weapon such as a gun or a sword in the security field.
【０００８】[0008]
【課題を解決するための手段】このため、請求項１記載
の発明の金属検知装置は、コイルと、励磁電源と、赤外
線検知カメラと、熱画像表示モニタと、を含んで構成
し、前記コイルには励磁電源が接続され、コイルに交番
電流を流すことにより、コイルに交番磁界が発生するよ
うに構成する一方、前記赤外線検知カメラは、コイルに
発生する交番磁界の作用範囲に向けて配設され、該赤外
線検知カメラによる検知信号が熱画像として前記熱画像
表示モニタにより表示するように構成した。Therefore, the metal detecting apparatus of the invention according to claim 1 comprises a coil, an exciting power source, an infrared ray detecting camera, and a thermal image display monitor. An excitation power source is connected to the coil, and an alternating magnetic field is applied to the coil to generate an alternating magnetic field. On the other hand, the infrared detection camera is arranged toward the range of action of the alternating magnetic field generated in the coil. Then, the detection signal from the infrared detection camera is displayed as a thermal image on the thermal image display monitor.
【０００９】請求項２記載の発明の金属検知装置は、前
記励磁電源の励磁周波数は可変とし、検知対象によって
励磁周波数を変化させて決定するようにした。According to another aspect of the metal detector of the present invention, the exciting frequency of the exciting power source is variable, and the exciting frequency is changed depending on the object to be detected.
【００１０】[0010]
【作用】交番磁界中にある金属物体は、磁界エネルギの
一部が金属物体の温度上昇として消費される（渦電流
損，ヒステリシス損）ため、その温度が上昇する。そし
て、金属の種類によって前記損失の程度にはかなりの差
があり、一般に鉄系の金属は損失が大きい。In the metal object in the alternating magnetic field, part of the magnetic field energy is consumed as a temperature rise of the metal object (eddy current loss, hysteresis loss), so that the temperature rises. Further, there is a considerable difference in the degree of the loss depending on the type of metal, and iron-based metals generally have a large loss.
【００１１】又、交番磁界の周波数も高い程損失が大き
い。従って、これらの性質を利用して、コイルに適当な
交番電流を流し、コイルの発生磁界領域を赤外線検知カ
メラで監視することによって、この交番磁界内に入るこ
とによって発熱した金属物体の形状を識別するように構
成することができる。Further, the higher the frequency of the alternating magnetic field, the larger the loss. Therefore, by utilizing these properties, an appropriate alternating current is passed through the coil, and the magnetic field region of the coil is monitored by an infrared detection camera to identify the shape of a metal object that has heated by entering the alternating magnetic field. Can be configured to.
【００１２】かかる原理に基づいた請求項１記載の発明
による金属検知装置によれば、例えば、遮蔽物を隔てて
コイルと反対側に位置する被検知金属物体を検知する場
合、コイルと赤外線検知カメラとを遮蔽物の外面に沿っ
て移動させる。被検知金属物体がコイルに発生する交番
磁界内に入った場合、被検知金属物体は加熱され、その
周囲との温度差が生じる。According to the metal detecting apparatus of the first aspect of the present invention based on such a principle, for example, when detecting a detected metal object located on the opposite side of the coil with a shield, the coil and the infrared detecting camera. And are moved along the outer surface of the shield. When the metal object to be detected enters the alternating magnetic field generated in the coil, the metal object to be detected is heated and a temperature difference from the surroundings is generated.
【００１３】従って、このとき赤外線検知カメラによる
検知信号が熱画像として熱画像表示モニタにより表示さ
れる。即ち、被検知金属物体の形状が熱画像表示モニタ
上の熱画像により表示されるため、遮蔽物で隔てられた
被検知金属物体の形状を含んだ検知が可能となる。Therefore, at this time, the detection signal from the infrared detection camera is displayed as a thermal image on the thermal image display monitor. That is, since the shape of the detected metal object is displayed by the thermal image on the thermal image display monitor, it is possible to perform detection including the shape of the detected metal object separated by the shield.
【００１４】又、遮蔽物が例えば人体である場合、つま
り人が被検知金属物体を携帯している場合にも、同様に
して携帯している被検知金属物体の形状を含んだ検知が
可能となる。Further, even when the shielding object is, for example, a human body, that is, when a person carries a metal object to be detected, it is possible to perform detection including the shape of the metal object to be detected, which is also carried. Become.
【００１５】請求項２記載の発明において、励磁電源の
励磁周波数は可変とし、検知対象によって励磁周波数を
変化させて決定することにより、検知能力が向上する。According to the second aspect of the invention, the exciting frequency of the exciting power supply is variable, and the exciting frequency is changed depending on the object to be detected, so that the detecting ability is improved.
【００１６】[0016]
【実施例】以下、添付された図面を参照して本発明を詳
述する。先ず、本発明に係る金属検知装置の原理につい
て説明する。交番磁界中にある金属物体は、磁界エネル
ギの一部が金属物体の温度上昇として消費される（渦電
流損，ヒステリシス損）ため、その温度が上昇する。そ
して、金属の種類によって前記損失の程度にはかなりの
差があり、一般に鉄系の金属は損失が大きい。又、交番
磁界の周波数も高い程損失が大きい。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. First, the principle of the metal detection device according to the present invention will be described. The temperature of the metal object in the alternating magnetic field rises because part of the magnetic field energy is consumed as a temperature rise of the metal object (eddy current loss, hysteresis loss). Further, there is a considerable difference in the degree of the loss depending on the type of metal, and iron-based metals generally have a large loss. Also, the higher the frequency of the alternating magnetic field, the greater the loss.
【００１７】従って、これらの性質を利用して、コイル
に適当な交番電流を流し、コイルの発生磁界領域を赤外
線検知カメラで監視することによって、この交番磁界内
に入ることによって発熱した金属物体の形状を識別する
ように構成することができる。Therefore, by utilizing these properties, an appropriate alternating current is caused to flow in the coil, and the magnetic field region of the coil is monitored by the infrared ray detection camera. It can be configured to identify the shape.
【００１８】かかる原理に基づいた金属検知装置の一実
施例を図１のブロック図に基づいて説明する。即ち、図
において、金属検知装置は、コイル１と、励磁電源２
と、赤外線検知カメラ３と、熱画像表示モニタ４とから
構成される。An embodiment of the metal detecting device based on the above principle will be described with reference to the block diagram of FIG. That is, in the figure, the metal detection device includes a coil 1 and an excitation power supply 2
And an infrared detection camera 3 and a thermal image display monitor 4.
【００１９】前記コイル１には励磁電源２が接続され、
コイル１に交番電流を流すことにより、コイル１に交番
磁界が発生するように構成される。An excitation power supply 2 is connected to the coil 1,
An alternating magnetic field is generated in the coil 1 by applying an alternating current to the coil 1.
【００２０】前記赤外線検知カメラ３は、コイル１に発
生する交番磁界の作用範囲に向けて配設され、この赤外
線検知カメラ３による検知信号が熱画像として熱画像表
示モニタ４により表示されるように構成される。The infrared detection camera 3 is arranged toward the range of action of the alternating magnetic field generated in the coil 1, and the detection signal from the infrared detection camera 3 is displayed as a thermal image on the thermal image display monitor 4. Composed.
【００２１】次に、かかる構成の金属検知装置の作用に
ついて説明する。遮蔽物５を隔ててコイル１と反対側に
位置する被検知金属物体６を検知する場合、コイル１と
赤外線検知カメラ３とを遮蔽物５の外面に沿って移動さ
せる。被検知金属物体６がコイル１に発生する交番磁界
内に入った場合、被検知金属物体６は加熱され、その周
囲との温度差が生じる。Next, the operation of the metal detecting device having such a structure will be described. When detecting the detected metal object 6 located on the opposite side of the coil 1 with the shield 5 interposed therebetween, the coil 1 and the infrared detection camera 3 are moved along the outer surface of the shield 5. When the metal object 6 to be detected enters the alternating magnetic field generated in the coil 1, the metal object 6 to be detected is heated and a temperature difference with the surroundings is generated.
【００２２】従って、このとき赤外線検知カメラ３によ
る検知信号が熱画像として熱画像表示モニタ４により表
示される。即ち、被検知金属物体６の形状が熱画像表示
モニタ４上の熱画像により表示されるため、遮蔽物５で
隔てられた被検知金属物体６の形状を含んだ検知が可能
となる。Therefore, at this time, the detection signal from the infrared detection camera 3 is displayed on the thermal image display monitor 4 as a thermal image. That is, since the shape of the detected metal object 6 is displayed by the thermal image on the thermal image display monitor 4, it is possible to detect the shape of the detected metal object 6 separated by the shield 5.
【００２３】又、遮蔽物が例えば人体である場合、つま
り人が被検知金属物体を携帯している場合にも、同様に
して携帯している被検知金属物体の形状を含んだ検知が
可能となる。Further, when the shield is, for example, a human body, that is, when a person carries a metal object to be detected, it is possible to perform detection including the shape of the metal object to be carried in the same manner. Become.
【００２４】尚、上記の検知装置において、その検知能
力を向上させるため、励磁電源２の励磁周波数は可変と
し、検知対象によって励磁周波数を変化させて決定する
のが好ましい。又、前記コイル１と赤外線検知カメラ３
とを一体化するのが望ましい。In the above detection device, in order to improve the detection capability, it is preferable that the excitation frequency of the excitation power supply 2 be variable and the excitation frequency be changed depending on the detection target. In addition, the coil 1 and the infrared detection camera 3
It is desirable to integrate and.
【００２５】かかる構成の金属検知装置によれば、従来
のＸ線を利用した検知装置のように検知物体の形状を識
別できる点で有効でありながら、装置が簡単かつコンパ
クトであるから、その取り扱いに制限がなく、又、装置
として安価であるという利点がある。According to the metal detecting device having such a structure, it is effective in that the shape of the detected object can be identified as in the conventional detecting device using X-rays, but the device is simple and compact. There is no limitation in the number, and there is an advantage that the device is inexpensive.
【００２６】従って、特に、被検知金属物体の形状を画
像として表示できるから、出入口において、例えば、銃
や刀剣類等の凶器の存在を監視するのに有効であり、社
会安全上有効である等、セキュリティ分野に有効利用す
ることができる。勿論、非金属中に混入した金属の検知
等も充分に効果を発揮する。Therefore, since the shape of the metal object to be detected can be displayed as an image, it is effective for monitoring the presence of a weapon such as a gun or a sword at the entrance, and is effective for social safety. , Can be effectively used in the security field. Of course, the detection of the metal mixed in the non-metal is sufficiently effective.
【００２７】[0027]
【発明の効果】以上説明したように、請求項１記載の発
明によれば、装置の取り扱いに制限がなく、又、装置と
して安価でありながら、金属物体等の形状を含んだ検知
が可能であり、特に、セキュリティ分野において、銃や
刀剣類等の凶器の存在を監視するのに有効な金属検知装
置を提供することができる。As described above, according to the invention as set forth in claim 1, there is no limitation on the handling of the device, and although the device is inexpensive, it is possible to detect the shape of a metal object or the like. In particular, in the security field, it is possible to provide a metal detection device effective for monitoring the presence of a weapon such as a gun or a sword.
【００２８】請求項２記載の発明によれば、励磁電源の
励磁周波数は可変とし、検知対象によって励磁周波数を
変化させて決定するようにしたから、検知能力が向上す
る。According to the second aspect of the invention, the exciting frequency of the exciting power source is variable, and the exciting frequency is changed depending on the object to be detected, so that the detecting ability is improved.
【図１】 請求項１及び２記載の発明の一実施例を示す
ブロック図FIG. 1 is a block diagram showing an embodiment of the invention described in claims 1 and 2.
１ コイル ２ 励磁電源 ３ 赤外線検知カメラ ４ 熱画像表示モニタ ５ 遮蔽物 ６ 被検知金属物体 1 coil 2 excitation power source 3 infrared detection camera 4 thermal image display monitor 5 shield 6 metal object to be detected
Claims (2)
と、熱画像表示モニタと、を含んで構成され、 前記コイルには励磁電源が接続され、コイルに交番電流
を流すことにより、コイルに交番磁界が発生するように
構成される一方、 前記赤外線検知カメラは、コイルに発生する交番磁界の
作用範囲に向けて配設され、該赤外線検知カメラによる
検知信号が熱画像として前記熱画像表示モニタにより表
示されるように構成されたことを特徴とする金属検知装
置。1. A coil, an excitation power supply, an infrared ray detection camera, and a thermal image display monitor are included, and the excitation power supply is connected to the coil, and an alternating current is passed through the coil to thereby apply the current to the coil. While the alternating magnetic field is configured to be generated, the infrared detection camera is arranged toward the range of action of the alternating magnetic field generated in the coil, and the detection signal from the infrared detection camera is the thermal image display monitor as a thermal image. A metal detection device characterized in that it is configured to be displayed.
知対象によって励磁周波数を変化させて決定することを
特徴とする請求項１記載の金属検知装置。2. The metal detection device according to claim 1, wherein the excitation frequency of the excitation power source is variable, and is determined by changing the excitation frequency depending on the object to be detected.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22079294A JPH0862340A (en) | 1994-08-24 | 1994-08-24 | Metal detecting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP22079294A JPH0862340A (en) | 1994-08-24 | 1994-08-24 | Metal detecting device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0862340A true JPH0862340A (en) | 1996-03-08 |
Family
ID=16756644
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP22079294A Pending JPH0862340A (en) | 1994-08-24 | 1994-08-24 | Metal detecting device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0862340A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100390656B1 (en) * | 2000-10-04 | 2003-07-07 | 주식회사 방산테크노로지 | security and reference device for an infrared rays |
| JP2008134177A (en) * | 2006-11-29 | 2008-06-12 | Matsushita Electric Ind Co Ltd | Object detection method for mobile device |
| CN103852801A (en) * | 2014-01-10 | 2014-06-11 | 凯迈(洛阳)电子有限公司 | Infrared gun on-line measurement device |
| CN112179497A (en) * | 2020-09-16 | 2021-01-05 | 安徽科杰粮保仓储设备有限公司 | AI technology-based campus personnel behavior abnormity early warning robot |
-
1994
- 1994-08-24 JP JP22079294A patent/JPH0862340A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100390656B1 (en) * | 2000-10-04 | 2003-07-07 | 주식회사 방산테크노로지 | security and reference device for an infrared rays |
| JP2008134177A (en) * | 2006-11-29 | 2008-06-12 | Matsushita Electric Ind Co Ltd | Object detection method for mobile device |
| CN103852801A (en) * | 2014-01-10 | 2014-06-11 | 凯迈(洛阳)电子有限公司 | Infrared gun on-line measurement device |
| CN112179497A (en) * | 2020-09-16 | 2021-01-05 | 安徽科杰粮保仓储设备有限公司 | AI technology-based campus personnel behavior abnormity early warning robot |
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