JP2510217B2 - Proximity switch device - Google Patents
Proximity switch deviceInfo
- Publication number
- JP2510217B2 JP2510217B2 JP62262276A JP26227687A JP2510217B2 JP 2510217 B2 JP2510217 B2 JP 2510217B2 JP 62262276 A JP62262276 A JP 62262276A JP 26227687 A JP26227687 A JP 26227687A JP 2510217 B2 JP2510217 B2 JP 2510217B2
- Authority
- JP
- Japan
- Prior art keywords
- oscillation
- electrode plate
- detection
- circuit
- oscillating
- 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.)
- Expired - Fee Related
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Description
【発明の詳細な説明】 〈産業上の利用分野〉 本発明は、主として人体等の物体が接近したのを非接
触で検知して自動開閉ドアや防犯装置の作動を制御する
ための起動スイッチとして用いられる近接スイッチ装置
に関するものである。DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention is mainly used as a start switch for detecting the approach of an object such as a human body in a non-contact manner and controlling the operation of an automatic door and a security device. The present invention relates to a proximity switch device used.
〈従来の技術〉 斯かる自動開閉ドアを開閉制御する起動用スイッチと
して用いられる近接スイッチ装置としては、所定の間隙
で対置した２枚の金属板全体を防水用のゴムで被覆して
なるゴムマットスイッチが従来において一般に用いられ
ていた。このゴムマットスイッチは、この上に人体が乗
ることによる２枚の金属板の接触により接近する人体を
検知するもので、人体に対し接触式で検知するため、例
えば、ハイヒールやげたで踏まれた時に故障したり、防
水機能が破損したりし易く、寿命が短い欠点があるとと
もに、自動開閉ドアの近傍箇所に露呈状態で敷設される
ために、美観上好ましくない。<Prior Art> A proximity switch device used as a starting switch for controlling the opening and closing of such an automatic door is a rubber mat switch in which two metal plates facing each other at a predetermined gap are covered with waterproof rubber. Was generally used in the past. This rubber mat switch detects a human body approaching due to the contact of two metal plates caused by the human body riding on the rubber mat switch. Since it detects the human body by a contact type, for example, when a person is stepped on with high heels or a sled. It has a drawback that it is easy to break down or its waterproof function is damaged, its life is short, and it is laid out in an exposed state in the vicinity of the automatic opening / closing door.
そこで、このような欠点を解消した近接スイッチ装置
として、自動開閉ドアの近傍箇所のマット部の地中に金
属板からなる２枚の感知板を埋設し、この感知板を発振
回路の一部として使用して発振部に１〜20MHzの高周波
を発振させ、人体が埋設された感知板に近づくと、人体
と感知板との間の浮遊容量や抵抗損失等によって発振回
路の発振周波数が変化し、これによるＱの変化に従って
出力レベルが変化するので、この変化分を外部に取出し
てスイッチ部を作動させ、これによって自動開閉ドアを
開閉制御する非接触検知方式のものが案出されている。Therefore, as a proximity switch device that solves such drawbacks, two sensing plates made of metal plates are embedded in the ground of a mat portion near an automatic opening / closing door, and these sensing plates are used as a part of an oscillation circuit. When oscillating a high frequency of 1 to 20 MHz in the oscillating unit and approaching the sensing plate in which the human body is embedded, the oscillation frequency of the oscillating circuit changes due to stray capacitance and resistance loss between the human body and the sensing plate, Since the output level changes according to the change in Q due to this, a non-contact detection system has been devised in which this change is extracted to the outside and the switch unit is operated to open / close the automatic opening / closing door.
〈発明が解決しようとする問題点〉 然し乍ら、前記非接触検知方式の近接スイッチ装置に
おいても、金属板からなる２枚の感知板を発振回路の一
部として使用していることに起因して、以下のような種
々の問題点がある。即ち、発振部は感知板を発振回路の
一部として使用するため、発振部は感知板の近くに設置
するのが好ましく、発振部を感知板とともに地中に埋設
する場合には、感知板のインピーダンスの関係上、同一
電界内の感知板内部に入れて使用するのが一般的であ
る。このようにする理由は、発振部を感知板から引離す
と、インピーダンスの関係上から両者間を結ぶ給電線に
別の電界が生じ、感知板を発振回路の一部として使用で
きなくなるためである。<Problems to be Solved by the Invention> However, even in the proximity switch device of the non-contact detection system, two sensing plates made of metal plates are used as a part of the oscillation circuit. There are various problems as described below. That is, since the oscillating section uses the sensing plate as a part of the oscillating circuit, it is preferable to install the oscillating section near the sensing plate. Due to the impedance, it is generally used by putting them inside the sensing plate in the same electric field. The reason for doing this is that when the oscillating part is separated from the sensing plate, another electric field is generated in the power supply line connecting the sensing part due to the impedance, and the sensing plate cannot be used as a part of the oscillating circuit. .
ところが、感知板内に発振部を収めた構造にすると、
実用上大きな不便がある。即ち、発振部の不具合による
点検修理の場合、感知板全体を取外す必要があり、特に
タイル等のフロアを外すのは大掛かりな工事となる。ま
た、保守用の穴を予め設けておけば、前記問題点を解消
できるが、自動開閉ドアの正面にこのようなホールを設
けるのは、外観の美観上や通行の円滑さからも問題があ
る。さらに、感知板と発振部とを一体的に構成すること
により、装置の製作や信頼性の点に問題がある。However, if the structure where the oscillating part is housed in the sensing plate is used,
There is a big inconvenience in practical use. That is, in the case of inspection and repair due to a malfunction of the oscillating portion, it is necessary to remove the entire sensing plate, and especially removing the floor such as tiles is a large-scale work. Further, if a hole for maintenance is provided in advance, the above problem can be solved, but providing such a hole in front of the automatic opening / closing door has a problem in terms of aesthetic appearance and smooth passage. . Furthermore, by integrally forming the sensing plate and the oscillating unit, there are problems in manufacturing and reliability of the device.
〈発明の目的〉 本発明は、このような従来の技術的課題に鑑みなされ
たもので、埋設する電極板からなる検知部と発振部やス
イッチ部等からなる制御部とを任意に離して設置した場
合にも、両者間を接続するケーブル等の信号伝送線に不
要な電波が発生することのない近接スイッチ装置を提供
することを目的とするものである。<Purpose of the Invention> The present invention has been made in view of the above-described conventional technical problems, and a detection unit formed of an embedded electrode plate and a control unit formed of an oscillation unit, a switch unit, and the like are installed separately from each other. Even in such a case, it is an object of the present invention to provide a proximity switch device in which unnecessary radio waves are not generated in a signal transmission line such as a cable connecting the both.
〈問題点を解決するための手段〉 上記の目的を達成するために本発明の近接スイッチ装
置は、水晶振動子等から構成され所定の周波数信号を出
力する発振回路と、互いに近接して埋設され上記発振回
路の発振信号を出力するアンテナとして機能する一対の
発振用電極板と、この一方の発振用電極板に近接して埋
設されるとともに他方の発振用電極板に接続された検知
用電極板と、この検知用電極板と他方の発振用電極板と
の間の電界強度の一定レベル以上の変化を検出する検出
回路とを備えてなり、上記発振用電極板および検知用電
極板は、それぞれ対向配置された状態で積み重ねられて
いるとによって特徴付けられている。<Means for Solving the Problems> In order to achieve the above-mentioned object, the proximity switch device of the present invention is embedded in close proximity to an oscillation circuit configured of a crystal oscillator or the like and outputting a predetermined frequency signal. A pair of oscillation electrode plates that function as an antenna that outputs an oscillation signal of the oscillation circuit, and a detection electrode plate that is embedded near one of the oscillation electrode plates and is connected to the other oscillation electrode plate. And a detection circuit for detecting a change in electric field strength between the detection electrode plate and the other oscillation electrode plate at a certain level or higher, and the oscillation electrode plate and the detection electrode plate are respectively It is characterized by being stacked in a state of being opposed to each other.
〈作用〉 発振回路の発振信号が一対の発振用電極板を介して放
射出力されているため、３枚の電極板の周囲に電気力線
が発生する。検知用電極板および他方の発振用電極板に
よる電気力線は、これらの電極板を挟み込んだ形で回り
込み、外側に放射状に大きい電気力線となる。そして、
各電極板が埋設されている検知エリアに人体が接近する
と、３枚の電極板の各間隙の誘電率が然程変化しないこ
とによって電気力線も変化しないが、外側にそれぞれ位
置する検知用電極板および他方の発振用電極板の各外方
部分の誘電率が変化してその電気力線が変化し、この互
いに接続されている検知用電極板と他方の発振用電極板
間に、電界強度の変化によって電圧が誘起され、この誘
起電圧が一定値以上になると、それを検出回路が検出し
てスイッチ部を作動させる。<Operation> Since the oscillation signal of the oscillation circuit is radiated and output through the pair of oscillation electrode plates, lines of electric force are generated around the three electrode plates. The electric force lines generated by the detection electrode plate and the other oscillation electrode plate wrap around these electrode plates in a sandwiched manner, and become large electric force lines radially outward. And
When the human body approaches the detection area in which each electrode plate is embedded, the lines of electric force do not change because the dielectric constants of the gaps of the three electrode plates do not change so much, but the detection electrodes located on the outside, respectively. Of the plate and the other part of the oscillation electrode plate on the other side changes the electric lines of force and changes the electric field strength between the detection electrode plate and the other oscillation electrode plate connected to each other. A voltage is induced by the change of the voltage, and when the induced voltage exceeds a certain value, the detection circuit detects it and activates the switch section.
この近接スイッチ装置は、既存装置のように各電極板
が発振回路の構成要素の一つになっておらず、一対の発
振用電極板は発振回路の発振信号を出力する単なる電極
として作用し、発振周波数および出力レベルは発振回路
自体により決定されるため、各電極板と発振回路および
検出回路とを離して設置しても、これらの間を接続する
ケーブル等の信号伝送線に別の電界が生じない。In this proximity switch device, each electrode plate is not one of the constituent elements of the oscillation circuit unlike the existing device, and the pair of oscillation electrode plates act as simple electrodes for outputting the oscillation signal of the oscillation circuit. Since the oscillating frequency and output level are determined by the oscillating circuit itself, even if the electrode plates and the oscillating circuit and the detecting circuit are installed separately, another electric field will be generated in the signal transmission line such as the cable connecting them. Does not happen.
〈実施例〉 以下、本発明の好適な実施例について図面を参照しな
がら説明する。<Example> Hereinafter, a preferred example of the present invention will be described with reference to the drawings.
図は本発明の一実施例を示すブロック構成図で、検知
エリア、例えば自動開閉ドアの起動スイッチとして用い
る場合には自動開閉ドアの近傍箇所に埋設される検知部
は、単一の検知用電極板１および一対の発振用電極板2,
3が、発泡ウレタン系素材等の高誘電率を有するスペー
サ部材４を介在して積重された構成になっており、両外
側に位置する検知用電極板１とアース側発振用電極板３
とが互いに接続されている。この各電極板１〜３として
は、単なる金属板の他に綱状、格子状および柵状の各形
状のもの用いることができる。FIG. 1 is a block diagram showing an embodiment of the present invention. In a detection area, for example, when used as a start switch for an automatic opening / closing door, a detection unit embedded in the vicinity of the automatic opening / closing door is a single detection electrode. Plate 1 and a pair of oscillation electrode plates 2,
3 has a structure in which a spacer member 4 having a high dielectric constant, such as urethane foam material, is interposed and stacked, and the detection electrode plate 1 and the earth side oscillation electrode plate 3 located on both outer sides are stacked.
And are connected to each other. As each of the electrode plates 1 to 3, in addition to a simple metal plate, one having a rope shape, a grid shape, and a fence shape can be used.
発振回路５は、水晶振動子等を構成部品として構成さ
れて一定の発振周波数信号を出力するもので、発振信号
を一対の発振用電極板2,3を通じて出力する。即ち、両
発振用電極板2,3は、発振回路５の構成部材の一つでは
なく、発振回路５の単なるアンテナとして機能する。The oscillation circuit 5 is composed of a crystal oscillator or the like as a component and outputs a constant oscillation frequency signal. The oscillation circuit 5 outputs the oscillation signal through the pair of oscillation electrode plates 2 and 3. That is, the two oscillation electrode plates 2 and 3 do not function as one of the constituent members of the oscillation circuit 5, but merely function as an antenna of the oscillation circuit 5.
増幅回路７は、検知用電極板７とアース側発振用電極
板３との間の電界強度、つまり誘起電圧を増幅するもの
で、この増幅回路７の構成部材の一つである検知用コイ
ル６の１次側コイル部が検知用電極板１とアース側発振
用電極板３との間に介挿接続されているとともに、２次
側コイル部が増幅回路７に接続されている。The amplifier circuit 7 amplifies the electric field strength between the detection electrode plate 7 and the ground-side oscillation electrode plate 3, that is, the induced voltage, and is a detection coil 6 which is one of the constituent members of the amplification circuit 7. The primary side coil part is inserted and connected between the detection electrode plate 1 and the ground side oscillation electrode plate 3, and the secondary side coil part is connected to the amplifier circuit 7.
検出回路８は、増幅回路７の出力を予め定められた設
定レベルと比較して設定レベル以上になった時に信号出
力する。出力回路９は、自動開閉ドアを開閉制御するた
め等のスイッチ部を備え、検出回路８の出力によりスイ
ッチ部のリレーコイルに通電される。The detection circuit 8 compares the output of the amplifier circuit 7 with a predetermined set level, and outputs a signal when the output becomes equal to or higher than the set level. The output circuit 9 includes a switch unit for controlling the opening / closing of the automatic opening / closing door, and the output of the detection circuit 8 energizes the relay coil of the switch unit.
次に、前記実施例の動作について説明すると、発振回
路５からの一定周波数の発振出力が一対の発振電極板2,
3を通じて放射されていることにより、各電極板１〜３
の周囲には電気力線が発生している。そして、この各電
極板１〜３が埋設されている検知エリアに人体が接近す
ると、各電極板１〜３の各間隙の電気力線は、高誘電率
のスペーサ部材４の存在により誘電率が殆んど変化しな
いことに対応して変化しないが、両外側に位置する検知
用電極１とアース側発振用電極板３のそれぞれの外方側
の電気力線は、人体の接近による誘電率の変化に対応し
て変化する。そのため、この両電極板1,3間の電界強度
が変化し、検知用コイル６の１次側コイル部に誘起電圧
が発生するとともに、２次側コイル部から増幅して取り
出され、増幅回路７でさらに増幅される。人体が各電極
板１〜３のほぼ近くまで接近すると、増幅回路７の出力
レベルが検出回路８の設定レベル以上となり、検出回路
８から信号出力されて出力回路９のリレーコイルに通電
され、自動開閉ドアが開けられる。Next, the operation of the above-described embodiment will be described. When the oscillation output from the oscillation circuit 5 has a constant frequency,
By being radiated through 3, each electrode plate 1-3
Electric lines of force are generated around the. When the human body approaches the detection area in which the electrode plates 1 to 3 are buried, the electric lines of force in the gaps of the electrode plates 1 to 3 have a dielectric constant due to the presence of the spacer member 4 having a high dielectric constant. The electric lines of force on the outer sides of the detection electrode 1 and the ground-side oscillation electrode plate 3, which are located on both outer sides, do not change in response to almost no change, but the electric lines of force of the dielectric constant due to the approach of the human body are Change in response to changes. Therefore, the electric field strength between the two electrode plates 1 and 3 changes, an induced voltage is generated in the primary side coil portion of the detection coil 6, and the amplified voltage is amplified and taken out from the secondary side coil portion. Is further amplified by. When the human body approaches each of the electrode plates 1 to 3, the output level of the amplifier circuit 7 becomes equal to or higher than the set level of the detection circuit 8, a signal is output from the detection circuit 8 and the relay coil of the output circuit 9 is energized, The open / close door can be opened.
この近接スイッチ装置は、既存装置のように電極板を
発振回路の構成部材の一つとして用いることによって人
体の接近による発振周波数のずれや強度の変化を検出す
るものと異なり、一対の発振用電極板2,3は発振回路５
のアンテナとして機能するのみであるから、各電極板１
〜３からなる検知部と、その他の発振回路５や検出回路
８等からなる制御部とを接続する信号伝送線の長さを任
意にすることができる。従って、近接スイッチ装置を配
設する現場での状況に合わせて、制御部を任意場所に取
付けることができるとともに、信号伝送線の配線場所も
任意に選択することができるものである。This proximity switch device differs from a device that detects a shift in the oscillation frequency or a change in intensity due to the approach of a human body by using an electrode plate as one of the constituent members of the oscillation circuit, as in the existing device, unlike a pair of oscillation electrodes. Plates 2 and 3 are oscillator circuits 5
Each electrode plate 1 because it only functions as an antenna
It is possible to arbitrarily set the length of the signal transmission line connecting the detection unit composed of 3 to 3 and the control unit composed of the other oscillation circuit 5, the detection circuit 8 and the like. Therefore, the control unit can be attached at an arbitrary place and the wiring place of the signal transmission line can be arbitrarily selected according to the situation at the site where the proximity switch device is installed.
尚、本発明は前記説明並びに図示例に限定されるもの
ではなく、請求の範囲を逸脱しない限り種々の変形実施
態様をも包含し得る。例えば、前記実施例では自動開閉
ドアの起動スイッチとして用いた場合について説明した
が、防犯用または安全用の機器における人体や移動物体
を検出するためのスイッチとして用いることもできる。
また、各電極板１〜３の間隙に介在するスペーサ部材４
は、発泡ウレタン系素材のものに限らず、他の高誘電率
の部材を用いてもよい。また、スペーサ部材４を介在さ
せずに空間としてもよい。The present invention is not limited to the above description and illustrated examples, and may include various modified embodiments without departing from the scope of the claims. For example, in the above-described embodiment, the case where the switch is used as a start switch for an automatic opening / closing door has been described, but the switch may be used as a switch for detecting a human body or a moving object in a crime prevention or safety device.
In addition, the spacer member 4 interposed in the gap between the electrode plates 1 to 3
Is not limited to the urethane foam material, and other high dielectric constant members may be used. Further, the space may be provided without interposing the spacer member 4.
〈発明の効果〉 以上説明したように、本発明の近接スイッチ装置によ
れば、一対の発振用電極板は発振回路の発振信号を出力
するアンテナとして機能し、一方の発振用電極板に近接
して埋設され、他方の発振用電極板に接続された検知用
電極板と、この検知用電極板と他方の発振用電極板との
間の電界強度の一定レベル以上の変化を検出する検出回
路とを備え、これらの発振用電極板および検知用電極板
を、それぞれ対向配置した状態で積み重ねた構成とした
ので、検知用電極板と他方の発振用電極板との間に生じ
る電気力線によって、人体等による容量変化を地面から
遠い範囲まで検出でき、高い感度を有する装置となる。
したがって、通常の歩行状態は勿論、例えば松葉杖によ
って移動する人についても、電気的出力を十分得ること
ができ、装置の動作が不安定となることもない。さら
に、各電極板からなる検知部と発振回路や検出回路等か
らなる制御部とを接続する信号伝送線の長さに影響され
なくなり、制御部の設置箇所および信号伝送線の配線を
任意に選択でき、点検修理等に容易に対応できる。<Effects of the Invention> As described above, according to the proximity switch device of the present invention, the pair of oscillation electrode plates function as antennas that output the oscillation signal of the oscillation circuit, and are close to one of the oscillation electrode plates. A detection electrode plate embedded in the other oscillation electrode plate, and a detection circuit for detecting a change in electric field strength between the detection electrode plate and the other oscillation electrode plate above a certain level. Since, the electrode plate for oscillation and the electrode plate for detection are stacked in a state of being arranged facing each other, by the electric force line generated between the electrode plate for detection and the other electrode plate for oscillation, The device has a high sensitivity because it can detect a capacitance change due to a human body or the like in a range far from the ground.
Therefore, not only in a normal walking state, but also in a person who moves with a crutch, for example, a sufficient electric output can be obtained, and the operation of the device does not become unstable. Furthermore, it is not affected by the length of the signal transmission line that connects the detection unit consisting of each electrode plate and the control unit consisting of the oscillation circuit and detection circuit, etc., and the installation location of the control unit and the wiring of the signal transmission line can be selected arbitrarily. It is possible to deal with inspections and repairs easily.
また、発振回路によってのみ発振周波数や出力レベル
が決定されるので、誤動作等のない安定した動作を行な
う。さらに、検知感度の調整を、発振の同調を何ら考慮
することなく、検出回路自体の検出感度またはこれの前
段の増幅回路の増幅度等の検出側の感度のみの調整によ
り行な得るので、非常に容易となる。Further, since the oscillation frequency and the output level are determined only by the oscillation circuit, stable operation without malfunction is performed. Furthermore, the detection sensitivity can be adjusted only by adjusting the detection sensitivity of the detection circuit itself or the sensitivity of the detection circuit such as the amplification degree of the amplification circuit in the preceding stage without considering oscillation tuning. It will be easier.
図は本発明の一実施例のブロック構成図である。 １……検知用電極板 ２……一方の発振用電極板 ３……他方の発振用電極板 ５……発振回路 ８……検出回路 The drawing is a block diagram of an embodiment of the present invention. 1 ... Detection electrode plate 2 ... One oscillation electrode plate 3 ... Other oscillation electrode plate 5 ... Oscillation circuit 8 ... Detection circuit
Claims (1)
号を出力する発振回路と、互いに近接して埋設され上記
発振回路の発振信号を出力するアンテナとして機能する
一対の発振用電極板と、この一方の発振用電極板に近接
して埋設されるとともに他方の発振用電極板に接続され
た検知用電極板と、この検知用電極板と他方の発振用電
極板との間の電界強度の一定レベル以上の変化を検出す
る検出回路とを備えてなり、上記発振用電極板および検
知用電極板は、それぞれ対向配置された状態で積み重ね
られていることを特徴とする近接スイッチ装置。1. An oscillating circuit composed of a crystal oscillator or the like for outputting a predetermined frequency signal, and a pair of oscillating electrode plates embedded in proximity to each other and functioning as antennas for outputting an oscillating signal of the oscillating circuit. The detection electrode plate that is embedded near the one oscillation electrode plate and is connected to the other oscillation electrode plate, and the electric field strength between the detection electrode plate and the other oscillation electrode plate. A proximity switch device, comprising: a detection circuit for detecting a change of a certain level or more, wherein the oscillation electrode plate and the detection electrode plate are stacked in a state of being opposed to each other.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62262276A JP2510217B2 (en) | 1987-10-16 | 1987-10-16 | Proximity switch device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62262276A JP2510217B2 (en) | 1987-10-16 | 1987-10-16 | Proximity switch device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01103318A JPH01103318A (en) | 1989-04-20 |
| JP2510217B2 true JP2510217B2 (en) | 1996-06-26 |
Family
ID=17373546
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62262276A Expired - Fee Related JP2510217B2 (en) | 1987-10-16 | 1987-10-16 | Proximity switch device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2510217B2 (en) |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS4528842Y1 (en) * | 1968-02-12 | 1970-11-06 |
-
1987
- 1987-10-16 JP JP62262276A patent/JP2510217B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01103318A (en) | 1989-04-20 |
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