JPS6033035A - Light damping type smoke detector - Google Patents
Light damping type smoke detectorInfo
- Publication number
- JPS6033035A JPS6033035A JP14141783A JP14141783A JPS6033035A JP S6033035 A JPS6033035 A JP S6033035A JP 14141783 A JP14141783 A JP 14141783A JP 14141783 A JP14141783 A JP 14141783A JP S6033035 A JPS6033035 A JP S6033035A
- Authority
- JP
- Japan
- Prior art keywords
- light
- smoke
- output
- receiving element
- light source
- 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
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/47—Scattering, i.e. diffuse reflection
- G01N21/49—Scattering, i.e. diffuse reflection within a body or fluid
- G01N21/53—Scattering, i.e. diffuse reflection within a body or fluid within a flowing fluid, e.g. smoke
- G01N21/534—Scattering, i.e. diffuse reflection within a body or fluid within a flowing fluid, e.g. smoke by measuring transmission alone, i.e. determining opacity
Landscapes
- Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Life Sciences & Earth Sciences (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Biochemistry (AREA)
- General Health & Medical Sciences (AREA)
- General Physics & Mathematics (AREA)
- Immunology (AREA)
- Pathology (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Fire-Detection Mechanisms (AREA)
Abstract
Description
【発明の詳細な説明】
本発明は、火災時に流入した煙による光源からの光の減
衰を受光部で感知して火災を検出するようにした減光式
煙感知器に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a dimming type smoke detector that detects a fire by sensing attenuation of light from a light source by smoke flowing in at the time of a fire.
従来、煙感知器としては、イオン化式の煙感知器、散乱
光式煙感知器が広く使用されている。Conventionally, ionization type smoke detectors and scattered light type smoke detectors have been widely used as smoke detectors.
しかしながら、イオン化式煙感知器は着炎火災のように
^温で発生ずる煙に対しては敏感に作動するが燻焼火災
のような低温燃焼で発生16煙に対しては充分な検出特
性が得られず、一方、散乱光式煙感知器は白色の煙に対
しては敏感に作動Jるが黒色の煙に対しては充分な検出
特性が得られないという欠点がある。However, although ionization smoke detectors are sensitive to smoke generated at high temperatures such as ignition fires, they do not have sufficient detection characteristics for smoke generated from low temperature combustion such as smoldering fires. On the other hand, the scattered light type smoke detector has the disadvantage that although it operates sensitively for white smoke, it cannot obtain sufficient detection characteristics for black smoke.
これに対し、煙による光源からの光の減只を検知づる減
光式煙感知器にあっては、着炎火災、燻焼火災、白色煙
をともなう火災、黒色煙を伴なう火災のいずれに対して
も一様に煙濃度に応じた検出特性が得られ、煙感知器と
しては最も利用価値が高い。On the other hand, dimming type smoke detectors that detect the dimming of light from a light source due to smoke detect any of the following: flaming fires, smoldering fires, fires with white smoke, and fires with black smoke. Detection characteristics uniformly correspond to smoke density, and it has the highest utility value as a smoke detector.
しかしながら、減光式煙感知器の欠点は、光源から受光
部までの光路長を長くとらなければ受光素子の温度変化
による出力変化を上回る受光出力を得ることかできない
点にある。However, a drawback of dimming type smoke detectors is that unless the optical path length from the light source to the light receiving section is made long, it is not possible to obtain a light receiving output that exceeds the output change due to temperature change of the light receiving element.
第1図はランベルト−ベアの法則に基づき光路長に対す
る受光量(受光出力)の変化率を煙濃度をパラメータと
して示したグラフであり、第2図に光路長が短いときの
特性を取り出して示している。Figure 1 is a graph showing the rate of change in the amount of received light (received light output) with respect to the optical path length based on the Lambert-Baer law, using the smoke concentration as a parameter, and Figure 2 shows the characteristics when the optical path length is short. ing.
ここで、例えば20%/mの煙濃度で火災を検出しよう
とすると、光路長5 ’c rnでは約1.11%の受
光用の変化が得られる。これに対し受光素子として例え
ばフォトダイオードを使用したとすると、フォトダイオ
ードの温度依存性は通常0゜14〜0.2%/℃稈瓜で
あり、使用温度範囲となる一り0℃〜→−50℃での受
光出力の変化率の絶対値20’Cを基準としたときは
10.14〜0.2%/℃IX(±30℃)−4,2〜
6%
となり、感知器の設置状態における温度変化で20%の
煙81度による受光量の変化率を越える変化を起してし
まう。従って、温度の影響を無視Jるためには、第1図
のグラフから25cm以上の光路長を確保しな【ノれば
ならない。For example, when trying to detect a fire at a smoke density of 20%/m, a change in light reception of about 1.11% is obtained with an optical path length of 5' crn. On the other hand, if a photodiode is used as a light-receiving element, the temperature dependence of the photodiode is usually 0°14 to 0.2%/°C, and the operating temperature range is 0°C to →- Absolute value of change rate of received light output at 50°C When referenced to 20'C, 10.14~0.2%/°C IX (±30°C) -4.2~
6%, and a temperature change in the installed state of the sensor causes a change that exceeds the rate of change in the amount of light received due to 20% smoke at 81 degrees Celsius. Therefore, in order to ignore the influence of temperature, it is necessary to ensure an optical path length of 25 cm or more from the graph of FIG.
そこで、従来の光源と受光部を同じ筐体内に設けた所謂
スポット式の減光式煙感知器では、光源からの光をミラ
ーで数回反射させて受光部に入射させ、例えば80cm
という実光路長を得るようにしたものもあるが、それで
も感知器の直411J20cmを越える大きさとなり、
通常のイオン化式および散乱光式の煙感知器が山径5〜
10cm程度であることと比較すると、感知器としては
大き過ぎて見栄えが悪く、またコスト的にも高価Cある
ため特殊な用途にしか利用できないという欠点があった
。Therefore, in the so-called spot-type dimming type smoke detector in which a conventional light source and a light receiving part are provided in the same housing, the light from the light source is reflected several times by a mirror and then incident on the light receiving part, for example, at a distance of 80 cm.
Although some devices have been designed to obtain an actual optical path length of
Regular ionization type and scattered light type smoke detectors have a mountain diameter of 5 or more.
Compared to the size of about 10 cm, it is too large to be used as a sensor, making it unsightly, and it is also expensive, so it can only be used for special purposes.
一方、実開昭53−112’474Mに示されるように
、受光素子を2個設け、一方の受光素子には煙により減
衰された光源からの光を入射し、他方の受光素子には光
源からの光をそのまま基準光として入射し、受光出力の
差から火災を検出す−るようにした減光式煙感知器も知
られているが、前述したJ:うにフィトダイオードの温
度依存性は、0.14〜0.2%/℃であることから、
最大0゜06%/℃となる素子のバラツキがあり、これ
に使用温度範囲・となる20±30℃を考慮すると、2
0%/111の煙濃度で±30℃の湿度変化により1.
8%の受光出力変化を起すこととなり、この影響を無視
り゛るためには信号変化量ΔV b<温度変化小1゜8
%の10倍以上、即ち△V=18%程度ないと良好な感
度を有する感知器とは言えないから光路長としては約8
0cmを必要とし、更に各受光素子毎に設()た増幅器
の特性のバラツキを考慮すると、従来のイオン化式およ
び散乱光式煙感知器に相当す゛る人ささの減光式煙感知
器を得ることは困難であった。On the other hand, as shown in Utility Model Application No. 53-112'474M, two light-receiving elements are provided, one light-receiving element receives light from a light source that is attenuated by smoke, and the other light-receiving element receives light from a light source. There is also a dimming type smoke detector that detects fire from the difference in the received light output by directly inputting the light as a reference light, but the temperature dependence of the J: sea urchin phytodiode mentioned above is Since it is 0.14 to 0.2%/°C,
There is a maximum variation of 0°06%/°C in the elements, and considering the operating temperature range of 20 ± 30°C, 2.
1 due to a humidity change of ±30°C at a smoke density of 0%/111.
This will cause a change in the received light output of 8%, and in order to ignore this effect, the signal change amount ΔV b < small temperature change 1°8
% or more, that is, about △V=18%, it cannot be said that the sensor has good sensitivity, so the optical path length is about 8.
0 cm, and considering the variation in the characteristics of the amplifier installed for each light-receiving element, it is possible to obtain a human-sized dimming type smoke detector that is equivalent to conventional ionization type and scattered light type smoke detectors. was difficult.
本発明は、このような従来の問題点に鑑みてなされたも
ので、イオン化式および散乱光式煙感知器と同等の大き
さとしても受光素子の温度依/i: +Lに影響される
ことなく設定感度に応じた濃度の煙を検出することので
きる減光式煙感知器を提供り。The present invention was made in view of such conventional problems, and even if the size is equivalent to that of ionization type and scattered light type smoke detectors, the temperature dependence of the light receiving element is not affected by /i: +L. We offer dimming type smoke detectors that can detect smoke with a concentration according to the sensitivity setting.
ることを目的とする。The porpose is to do.
この目的を達成するため本発明は、流入した煙により減
衰された光源からの光を検出(る第1の受光素子と煙の
影響を受けない光路を介して送られた光源からの光を検
出する第2の受光素子を有し、この第1および第2の受
光素子は同一ウニバー上に形成された光半導体構造をも
つ湿態特性の揃った素子であり、この第1および第2の
受光素子を両者の光電流の差に応じた信号が印加される
ように単一の演算増幅器(オペアンプ)に入力接続し、
演算増幅器には入力信号レベルが設定感度に応じた所定
レベルに達したときに出力を生じきせる感度設定手段(
オフセラ1〜調整回路)を設けるJこうにしたちのCあ
る。To achieve this objective, the present invention detects the light from the light source that is attenuated by the inflowing smoke (the first light receiving element detects the light from the light source that is attenuated by the inflowing smoke) and detects the light from the light source that is sent through an optical path that is not affected by the smoke. The first and second light receiving elements are elements having an optical semiconductor structure formed on the same unibar and having the same wet characteristics. The input of the element is connected to a single operational amplifier (op-amp) so that a signal corresponding to the difference in photocurrent between the two is applied.
The operational amplifier has a sensitivity setting means (which produces an output when the input signal level reaches a predetermined level according to the set sensitivity).
Off-celler 1~Adjustment circuit)
以下、本発明の実施例を図面に基づいて説明する。Embodiments of the present invention will be described below based on the drawings.
第3図は本発明の一実施例を感知器回路と共に示した説
明図である。FIG. 3 is an explanatory diagram showing one embodiment of the present invention together with a sensor circuit.
まず、構成を光学系について説明すると、1は光源とな
る発光ダイオードであり、感知器筐体内に形成された外
部J:りの煙が流入する検煙領域2に向けて光を送出す
る。発光ダイオード1と検煙領域2を介して相対した位
置には第1の受光素子となるフォトダイオード3が設置
され、フy+I〜ダイオード3に対しては入射側に設置
したスリット4の開口部を介して検煙領域2を通過した
発光ダ・+’A−ドIにりの光が入射す゛るようにして
いる。First, the configuration of the optical system will be described. Reference numeral 1 denotes a light emitting diode that serves as a light source, and emits light toward a smoke detection area 2 formed inside the sensor housing into which smoke from the outside flows. A photodiode 3 serving as a first light-receiving element is installed at a position facing the light-emitting diode 1 through the smoke detection area 2, and an opening of a slit 4 installed on the incident side is connected to the photodiode 3. The light from the light emitting diode +'A-domain I that has passed through the smoke detection area 2 is made incident through the smoke detection area 2.
一方、発光ダイオード1から検煙領11!2を通ってフ
ォトダイオード3に入射する光の経路から独立して光フ
ァイバー5により発光ダイオード1かIうの光を同じく
スリット4を介して第2の発光素子としてのフォトダイ
オード6に入用する光の経路が設けられている。尚、こ
のような減光式の光学系において、スリット4はフA1
〜ダイΔ−ド33゜6にぼぽ密着して設けられることか
ら、光路良化は発光ダイオード1とスリッ1〜4の間隔
で与えられる。On the other hand, independently of the path of the light that enters the photodiode 3 from the light-emitting diode 1 through the smoke detection area 11!2, the light from the light-emitting diode 1 or I is transmitted through the slit 4 to a second light source by the optical fiber 5. A path for light entering the photodiode 6 as an element is provided. In addition, in such a dimming type optical system, the slit 4 is connected to the frame A1.
Since it is provided in close contact with the diode 33°6, the optical path is improved by the distance between the light emitting diode 1 and the slits 1 to 4.
発光ダイオード1よりの光を検煙領域2を介して入射し
たフ、t l−ダイオード3と、光ファイバー5を介し
て直接入射したフォ1−ダイオード6は、カソード側の
共通接続をもって直列接続されており、このフォトダイ
オード3.6どしては、同一ウニバー上に隣接して配置
された素子44造を右するものが使用され、同一ウ]バ
ー」−に形成され−(いることから、フォトダイオード
3.6の温度特性を略同−にすることができる。この同
一ウゴハー上に)A]−ダイオード3.6を隣接して形
成し ゛た素子としては、例えば光電子工業株式会社製
の5P−2−29等を用いることができ、素子自体でカ
ソード側を共通接続したフオトダイオード3゜6の逆直
列接続が行なわれており、光入力を受けt−フォトダイ
オード3.6の各光電流の差電流を得ることができる。A photodiode 3 into which the light from the light emitting diode 1 enters through the smoke detection area 2 and a photodiode 6 into which the light enters directly via the optical fiber 5 are connected in series with a common connection on the cathode side. The photodiodes 3.6 and 44 are arranged adjacently on the same unibar, and are formed on the same unibar. The temperature characteristics of the diodes 3.6 can be made almost the same.As an element in which the diodes 3.6) are formed adjacently on the same substrate, for example, 5P manufactured by Kodenshi Kogyo Co., Ltd. -2-29 etc. can be used, and the element itself is connected in anti-series with photodiodes 3.6 whose cathodes are commonly connected. It is possible to obtain a difference current of .
この同一ウニバーに隣接して配置された2つのフーii
〜ダイA−ド3.6の光入力に夕・1する相対出力変化
は、O〜+50℃の範囲で0.1±0.035%以下と
なることが実験的に確認されている。従って、煙感知器
の使用温度となる一10〜+50℃の温度範囲における
フオ;−ダイA−ド3,6の相対出力の変化量が0.1
%以内であるとJ−れば、この影響を無視Jるために(
91信号変化吊ΔVが温度変化司1.0%の10倍以上
、即ちΔv=i、o%程度あれば良好な感度を右Jる感
知器が1qられ、ΔV=1.0%に対する光路長は第2
図のグラフから約5cmとなる。Two Fu II located adjacent to this same Univer
It has been experimentally confirmed that the relative output change due to the optical input of the diode 3.6 is 0.1±0.035% or less in the range of 0 to +50°C. Therefore, the amount of change in relative output of diodes 3 and 6 is 0.1 in the temperature range of -10 to +50°C, which is the working temperature of the smoke detector.
If it is within %, then in order to ignore this effect,
91 A sensor has good sensitivity if the signal change rate ΔV is 10 times or more than the temperature change of 1.0%, that is, Δv = i, o%, and the optical path length for ΔV = 1.0%. is the second
From the graph in the figure, it is approximately 5 cm.
また、同じ光源としての発光ダイオード1よりの光をフ
ォトダイA−ドダイA−ド3.6に入射しでいることか
ら、光源劣化に対しても差電流として得られるフオトダ
イオード3.6の相対出力は変化せず、温度変化に対し
ても安定した相対出力が得られると共に、光源劣化に対
しても同様に安定した相対出力を得ることができる。Furthermore, since the light from the light emitting diode 1, which serves as the same light source, is incident on the photodiode A and the photodiode A, the relative current of the photodiode 3.6 obtained as a difference current can also be used against deterioration of the light source. The output does not change, and a stable relative output can be obtained even with temperature changes, and a similarly stable relative output can be obtained even with light source deterioration.
次に、感知器回路を説明すると、温度および光源劣化に
対する相対出力の安定度が高いフォ1−ダイオード3.
6のカソード側の共通接続にJ:り電気的には差動回路
を形成しており、この)A1−ダイオード3.6の差動
回路で得られlc光雷電流にを増幅するため、フォトダ
イオード3,6のアノード側をオペアンプ7に入力接続
し“(いる。このオペアンプ7の入力回路において、)
AトタイA−ド6のアノード側はオペアンプ7のプラス
入力端子と接続され、回路のマイナス側に接続される。Next, the sensor circuit will be explained. The sensor circuit consists of a photodiode 3.
A differential circuit is electrically formed by the common connection on the cathode side of the A1-diode 3.6. The anode sides of diodes 3 and 6 are input connected to operational amplifier 7.
The anode side of the A-tie A-domain 6 is connected to the plus input terminal of the operational amplifier 7, and is connected to the minus side of the circuit.
また、オペアンプ7のマイナス入力端子にはノA]−ダ
イオード3のアノード側を接続し、且つ帰還抵抗R3を
介して出力を帰還接続している1、即も、フォトダイオ
ード3,6の差電流に比例しl、二人力電圧をオペアン
プ7に印加する回路接続を行なっている。In addition, the negative input terminal of the operational amplifier 7 is connected to the anode side of the diode 3, and the output is connected as a feedback via the feedback resistor R3. A circuit connection is made to apply a voltage proportional to 1 to the operational amplifier 7.
一方、オペアンプ7にはオフセット調整用の可変抵抗V
Rが設けられ、所定の煙濃度例えば減光率が15%/m
(2秤感麿)となる煙の流入によりjqられたフォト
ダイオード3,6の差電流に対応した入力電圧ににる出
力がLレベルとなるように可変抵抗VRを調整しておく
ことにより、15%/■を越える濃度の煙に対しオペア
ンプ7が1−ルーベル出ノjを生ずる感度設定を行なう
ことができる。尚、オフセット調整により設定した検出
感度でオペj′ンプ7がl−ルベル出力を生ずるコンパ
レータとして作動するためには、帰還抵抗R3の抵抗値
を充分大きくしておけばよい。また、煙濃度に応じたア
ナログ出力を1qたいときには、帰還抵抗R3の値を小
さくすることによりフォトダイオード3.6の差電流に
比例した検出出力を得ることができる。On the other hand, the operational amplifier 7 has a variable resistor V for offset adjustment.
R is provided, and a predetermined smoke density, for example, a light attenuation rate of 15%/m
By adjusting the variable resistor VR so that the output corresponding to the input voltage corresponding to the difference current between the photodiodes 3 and 6 that is jq due to the inflow of smoke becomes L level, Sensitivity settings can be made such that the operational amplifier 7 produces a 1-Rubel output no.j for smoke having a concentration exceeding 15%/■. Incidentally, in order for the operational j' amplifier 7 to operate as a comparator that produces an l-level output with the detection sensitivity set by the offset adjustment, the resistance value of the feedback resistor R3 should be made sufficiently large. Furthermore, when it is desired to increase the analog output according to the smoke density by 1q, by reducing the value of the feedback resistor R3, a detection output proportional to the difference current of the photodiode 3.6 can be obtained.
このように、第3図の感知器回路では111−のオペア
ンプ7によりフォトダイオード3,6の光゛電変換で得
られた差電流を電流電圧変換増幅でる回路構成どしてい
るため、各フy+1−ダイオード3゜6毎にオペアンプ
を用いた場合に比べ′Aオペアンプ互間の特性のバラツ
キを起こさず、フォトダイオード3.6の相対出力のバ
ラツキのみに依存した増幅出力を得ることができ、また
H>f変抵抗V Rによるオフセット調整のみで検出感
度を決めていることから、フォトダイオード3,6にλ
・1?lる光学系の機械的な調整を不要にりることがで
きる。In this way, the sensor circuit of FIG. 3 has a circuit configuration in which the operational amplifier 111- is used to convert and amplify the difference current obtained by photoelectric conversion of the photodiodes 3 and 6, so that each filter Compared to the case where an operational amplifier is used for every 3.6 diodes of y+1-, it is possible to obtain an amplified output that depends only on the variation in the relative output of the photodiode 3.6 without causing variations in the characteristics between the 'A operational amplifiers. In addition, since the detection sensitivity is determined only by offset adjustment by H>f variable resistor V R, photodiodes 3 and 6 have λ
・1? This eliminates the need for mechanical adjustment of the optical system.
次に、光学系の光路長B、についで1j、例えば第2図
に示した減光率20%/mにa3りる光路長F〕cmの
ときの受光素子の変化率ΔVは1 、 11%となるが
、2つのフォトダイオード3.6にJ:る相対出力の温
度変化量が一10〜+50℃の範囲で゛僅かに0.1%
にすぎず、この温度変化ff10.1%を無視するため
の信号変化量ΔVは10倍以上の例えば1.0%となり
、第2図のグラフから光路長5cmを満足する。従って
、光路長を短くすることにより変化率ΔVが小さくとも
温度による影響を無視でき、更に、オペアンプ7の増幅
率を適宜に設定するとにより煙の流入により得られるフ
ッ1トダイオード3の光電流の僅かな変化を高精度で検
出°す゛ることができる。従って、第3図の実施例によ
れば、従来のイオン化式および散乱光式煙感知器と同等
の大きさをもつ光路長化−1Qcm以下の減光式煙感知
器を実現することができる。Next, when the optical path length B of the optical system is 1j, for example, the optical path length F]cm when the light attenuation rate is 20%/m shown in FIG. 2, the rate of change ΔV of the light receiving element is 1, 11 %, but the temperature change in the relative output of the two photodiodes 3.6 is only 0.1% in the range of -110 to +50°C.
Therefore, the signal change amount ΔV to ignore this temperature change ff10.1% is 10 times or more, for example, 1.0%, which satisfies the optical path length of 5 cm from the graph of FIG. Therefore, by shortening the optical path length, even if the rate of change ΔV is small, the effect of temperature can be ignored. Furthermore, by appropriately setting the amplification factor of the operational amplifier 7, the photocurrent of the foot diode 3 obtained by the inflow of smoke can be reduced. Slight changes can be detected with high precision. Therefore, according to the embodiment shown in FIG. 3, it is possible to realize a dimming type smoke sensor having an optical path length of -1Qcm or less and having the same size as conventional ionization type and scattered light type smoke detectors.
第4図は、本発明で用いる同一ウユバー状に2つのフォ
トダイオードを形成した素子接続の他の実施例を示した
もので、第4図<a >は第3図と逆にノA1−ダイオ
ード3,6のアノード側を共通接続して差動出力が得ら
れるようにしたものであり、同図(b)はフォトダイオ
ード3,6を逆向きに並列接続した差動回路を示し、更
に、同図(C)はフォトダイオード3,6のアノード側
を共通端子とし、ノJンード側を個別に取り出した3端
子構造の差動回路としたもので、いずれの差動回路につ
いてもフオトダイオード3,6の差電流に応じた光電変
換出力を得ることができる。FIG. 4 shows another example of element connection in which two photodiodes are formed in the same shape used in the present invention. The anode sides of photodiodes 3 and 6 are commonly connected to obtain a differential output. Figure (b) shows a differential circuit in which photodiodes 3 and 6 are connected in parallel in opposite directions. The same figure (C) shows a differential circuit with a three-terminal structure in which the anode sides of photodiodes 3 and 6 are used as a common terminal, and the terminal sides of photodiodes 3 and 6 are taken out individually. , 6 can be obtained.
第5図は第3図の実施例を用いた減光式煙感知器の具体
的な回路構成の一例を示したもの(゛、端子8.9をも
って受信機より引き出された一対の電源兼用信号線に接
続され、受信機よりの電源供給を定電圧回路10で受(
プて瞬知器回路部に一定電圧を供給している。更に、第
5図の実力色例(よ発光ダイオード1のパルス発光覆る
方式を例にとることから、発振回路11が設りられ、発
振回路11の出力は抵抗R4を介しC発光ダイオード1
に供給され、また、抵抗R5および高周波成分遮断用の
インダクタンスLを介して]ンパレータどして作動する
オペアンプ7側の回路部に間欠的に市 源を供給J−る
ようにしている。発光ダイオート1よりの光は第3図の
実施例に示したように、検炸領域2を介してフォトダイ
オード3に入射すると共に、光ファイバー5による別の
光経路を介してフォトダイオードロに入射され、フォト
ダイオード3,6の差動出力はオペアンプ7に入力され
、検出感度はオペアンプ7に設けた可変抵抗VRによる
オフセット調整で設定されている。オペアンプ7の出力
はトランジスタ13.14でなる2段増幅回路に与えら
れ、トランジスタ14のコレクタより抵抗RIOを介し
てカウンタ12に入力接続され、カウンタ12は発振回
路1の発振パルスに同期し−C例えば2回のオペアンプ
7の検出出力が得られたときにカウンタ出力を生ずる。Fig. 5 shows an example of a specific circuit configuration of a dimming type smoke detector using the embodiment shown in Fig. 3. The constant voltage circuit 10 receives the power supply from the receiver (
A constant voltage is supplied to the instantaneous alarm circuit. Furthermore, since the example of actual color shown in FIG. 5 is taken as an example of the pulsed light emitting method of the light emitting diode 1, an oscillation circuit 11 is provided, and the output of the oscillation circuit 11 is connected to the C light emitting diode 1 through the resistor R4.
In addition, a natural source is intermittently supplied to the circuit section on the side of the operational amplifier 7 which operates as an amparator through a resistor R5 and an inductance L for cutting off high frequency components. As shown in the embodiment of FIG. 3, the light from the light emitting diode 1 is incident on the photodiode 3 via the detection area 2, and is also incident on the photodiode via another optical path formed by the optical fiber 5. The differential outputs of the photodiodes 3 and 6 are input to an operational amplifier 7, and the detection sensitivity is set by offset adjustment using a variable resistor VR provided in the operational amplifier 7. The output of the operational amplifier 7 is given to a two-stage amplifier circuit made up of transistors 13 and 14, and the collector of the transistor 14 is connected to the counter 12 via a resistor RIO. For example, a counter output is generated when the detection output of the operational amplifier 7 is obtained twice.
カウンタ出力はダイオードD1を介して端子8.9間接
続したリーイリスタ15のゲー1−にトリガ信号とし°
C供給され、4ノイリスタ15のターンオンにより帽子
8,9、即ち受信機よりの電源兼用信号線を低インピー
ダンスに短絡して発報電流を流すようにしている。尚、
サイリスタ15に並列接続されたツェナダイオードZD
およびコンデンサC1はサージ電圧およびノイズ吸収用
に設(Jている。The counter output is used as a trigger signal to the gate 1- of the Lee resistor 15 connected between terminals 8 and 9 through the diode D1.
When the four Noiristers 15 are turned on, the caps 8 and 9, that is, the power signal line from the receiver, are short-circuited to a low impedance, and an alarm current is caused to flow. still,
Zener diode ZD connected in parallel to thyristor 15
and capacitor C1 are provided for surge voltage and noise absorption.
この第5図の実施例による動作を簡単に説明りるならば
、発振回路11は一定周期毎に発光ダイオード1を間欠
発光しCおり、同時に発振回路11の発振パルスにより
オペ7ンブ7およびその出力段に設けたトランジスタ1
3.14の増幅回路に電源を供給し、発光ダイオード1
が発光する狛にパルス的な回路動作を行なっている。従
っ°C1発振回路11よりの発振パルス幅としては、抵
抗R5を介してのパルス信号を受りてからAペノ′ンブ
7を含む回路部が安定状態となるに充分なパルス幅をも
7Cせている。発光ダイオード1のパルス駆動により得
られた光は検煙領域を介しで)A1〜ダイオード3に入
射され、同時に光ノアイバーによる別の光経路を介して
フォトダイオード6にb入射し、フオトダイオード3,
6の光電流の差に応じた差動入力をオペアンプ7に与え
、検煙領域に対し煙の流入がないときには可変抵抗VR
によるオフセット調整によりオペアンプ7の出ノj(よ
Lレベルにあり、トランジスタ9.10がオフとなって
カウンタ12の泪数値はゼロとなって0る。To briefly explain the operation of the embodiment shown in FIG. 5, the oscillation circuit 11 causes the light emitting diode 1 to emit light intermittently at regular intervals, and at the same time, the oscillation pulses of the oscillation circuit 11 cause the operation circuit 7 and its Transistor 1 installed in the output stage
3. Supply power to the amplifier circuit of 14 and light emitting diode 1
A pulse-like circuit operation is performed on the light-emitting frame. Therefore, the oscillation pulse width from the C1 oscillation circuit 11 should be set to 7C, which is sufficient for the circuit section including the A pen block 7 to be in a stable state after receiving the pulse signal via the resistor R5. ing. The light obtained by pulse driving of the light emitting diode 1 is incident on A1 to diode 3 via the smoke detection area, and at the same time is incident on the photodiode 6 via another optical path by the optical noibar.
A differential input corresponding to the difference between the photocurrents of 6 and 6 is given to the operational amplifier 7, and when there is no smoke flowing into the smoke detection area, the variable resistor VR
Due to the offset adjustment, the output of the operational amplifier 7 is at the L level, the transistors 9 and 10 are turned off, and the value of the counter 12 becomes zero.
一方、検煙領域2に煙が流入した場合に1よ、流入した
煙if’、!痕に応じて)7It−ダイオード3に入射
する発光ダイオード1よりの光が減真し、可変抵抗VR
のオフセラl−調整で設定した検出感度、例えば減光率
15%/mの煙による受光出力が得られたときにオペア
ンプ7がHレベル出力を生じ、トランジスタ13.14
のオンにJ:リカウンタ12がカウントアツノ゛される
。続いて、次の発光ダイオ−1ζ1のパルス光について
も同様に15%/m以上どなる光の減衰を受(」たとき
には同様にオペアンプ7が1〜ルベル出力を生じ、カウ
ンタ12の、i1数値が設定した2カウントに達するこ
とでカウンタ12はナイリスタ15のゲートに出力を生
じ、サイリスタ15がトリガされることで受信機よりの
電源兼用信号線を低インピーダンスに短絡し、規定の発
報電流を受信機に流す。On the other hand, if smoke flows into smoke detection area 2, 1, if smoke flows in, ! 7It-The light from light emitting diode 1 that enters diode 3 decreases, and the variable resistor VR
When the detection sensitivity set by off-cellar l-adjustment is obtained, for example, the light reception output due to smoke with a light attenuation rate of 15%/m is obtained, the operational amplifier 7 generates an H level output, and the transistor 13.14
When J:recounter 12 is turned on, the counter 12 is counted up. Subsequently, when the pulsed light of the next light emitting diode 1ζ1 similarly receives a light attenuation of 15%/m or more, the operational amplifier 7 similarly generates a level output of 1 to 1, and the i1 value of the counter 12 becomes When the set count of 2 is reached, the counter 12 generates an output to the gate of the thyristor 15, which triggers the thyristor 15 to short-circuit the power signal line from the receiver to low impedance, and receives the specified alarm current. Run it into the machine.
次に、本発明の詳細な説明°すると、流入した煙により
減衰された光源からの光を検出する第1の受光素子と、
煙の影響を受りない光路を介しC送られた光源からの光
を検出する第2の受光素子を右し、この第1おにび第2
の受光素子は同一ウニバー上に形成された光半導体構造
をもつ温度特性の揃った素子であり、第1 d′3J:
び第2の受光素子を両者の光電流の差に応じたイハ弓が
印加されるように単一の演棹増幅器に入力接続し、演g
7i増幅器には入力信号レベルが設定感度に応じl≦所
定レベルに達したとぎに出力を生じさせる感度設定手段
を設けるようにしたため、2つの受光素子のHM (I
h変化に対する相対出力のバラツキは略無祝することか
でき、検煙領域を介して設りた光源と受光素 □子の光
路長’&10cm以下としても、2て)の受光素子の温
度に依存したバラツキの影響を受4−Jることなく流入
した煙濃度に応じた受光出力を得ることができ、この結
果、従来のイオン化式、散乱光式煙感知器と同等な10
cm以下の大きさをもつ減光式煙感知器を実用化するこ
とが可能となった。Next, the present invention will be described in detail. A first light receiving element detects light from a light source that is attenuated by inflowing smoke;
A second light-receiving element that detects light from a light source sent through an optical path unaffected by smoke is placed on the right, and this first and second
The light-receiving element is an element with an optical semiconductor structure formed on the same unibar and with uniform temperature characteristics, and the first d'3J:
and the second photodetector are input connected to a single arithmetic amplifier so that an I/A curve corresponding to the difference in photocurrent between the two is applied.
Since the 7i amplifier is equipped with a sensitivity setting means that generates an output when the input signal level reaches l≦a predetermined level according to the set sensitivity, the HM (I
Variations in the relative output with respect to h changes can be almost ignored, and even if the optical path length of the light source and photodetector installed through the smoke detection area is less than 10 cm, it depends on the temperature of the photodetector (2). It is possible to obtain a light receiving output according to the concentration of incoming smoke without being affected by the variation in smoke detectors.
It has become possible to put into practical use a dimming type smoke detector with a size of less than cm.
更に、2つの受光素子の差動出力を増幅する手段ど()
て、単〜の潰砕増幅器を使用していることから、各受光
素子毎に増幅器を設けた場合に比べ増幅器相互間の特性
のバラツキを無視することができ、光路長を短くするこ
とにより煙濃度に対づる受光出力の変化量が少なくなっ
ても、増幅器のυ!44のバラツキの影響を受(プるこ
となく減光量をi1確に検出することができる。Furthermore, means for amplifying the differential output of the two light receiving elements ()
Since a single crushing amplifier is used, variations in characteristics between amplifiers can be ignored compared to the case where an amplifier is provided for each photodetector, and smoke can be reduced by shortening the optical path length. Even if the amount of change in the received light output with respect to the concentration is small, the amplifier's υ! It is possible to accurately detect the amount of light attenuation without being affected by variations in the light intensity.
更に、潰砕増幅器のAフセツ1〜調整により検出感度を
設定しでいることから、減衰光と基準光を個別に入射し
た光学系における機械的な調整が不要となり、検出感度
の設定調整を極めて簡単に行7Jうことができる。Furthermore, since the detection sensitivity is set by adjusting the A-set of the crushing amplifier, there is no need for mechanical adjustment in the optical system where the attenuated light and the reference light are separately incident, making it possible to extremely easily adjust the detection sensitivity settings. You can easily do row 7J.
第1図は減光式煙感知器の光路長に対する光の変化量を
煙濃度をパラメータとして示したクラ−)図、第2図は
第1図の光路長の短い部分を取り出して示したグラフ図
、第3図は本発明の一実施例を示した説明図、第4図は
本発明で用いる2つのフォ1−ダイオードの差動接続の
他の実施例を示した回路図、第5図は第3図の実施例を
用いた減光式煙感知器の具体的実施例を示した回路図で
ある。
1:発光ダイオード(光源)
2:検煙領域
3:フォトダイオード(第1の受光素子)4ニスリット
5:光ファイバー
6:フォトダイオード(第2の受光素子)7:オペアン
プ
8.9=端子
10:定電圧回路
11:発振回路
12:カウンタ
13.14:l−ランジスタ
15:す゛イリスタ
特許出願人 ホーチキ株式会社
代理人 弁狸士 竹 内 進
第 1 図
L E&長(cm)Figure 1 is a graph showing the amount of change in light with respect to the optical path length of a dimming type smoke detector using smoke concentration as a parameter, and Figure 2 is a graph showing the short portion of Figure 1 with a short optical path length. 3 is an explanatory diagram showing one embodiment of the present invention, FIG. 4 is a circuit diagram showing another embodiment of differential connection of two photodiodes used in the present invention, and FIG. 3 is a circuit diagram showing a specific embodiment of a dimming type smoke detector using the embodiment of FIG. 3. FIG. 1: Light emitting diode (light source) 2: Smoke detection area 3: Photodiode (first light receiving element) 4 Nislit 5: Optical fiber 6: Photodiode (second light receiving element) 7: Operational amplifier 8.9 = terminal 10: Constant Voltage circuit 11: Oscillation circuit 12: Counter 13.14: L-Ran resistor 15: Suiristar Patent applicant Hochiki Co., Ltd. Agent Susumu Takeuchi 1 Figure L E & Length (cm)
Claims (1)
することを感知して火災信号を出ツノする減光式煙感知
器において、 煙によって減衰した光源からの光を検出する第1の受光
素子と、煙に影響されない光路を介して光源より送られ
た光を検出する第2の受光素子とを右し、該第1および
第2の受光素子は同一ウニバー上に形成された光半導体
構造を有する温度特性の揃った素子であり、該第1の受
光素子と第2の受光素子を両者の差電流に応じた信号を
印加するように演算増幅器に入力接続したことを特徴と
1−る減光式煙感知器。[Claims] In a dimming type smoke detector that detects that the light from the light source is attenuated by the light receiving part due to smoke flowing in during a fire and outputs a fire signal, A first light-receiving element for detecting light and a second light-receiving element for detecting light sent from a light source through an optical path unaffected by smoke are arranged on the right, and the first and second light-receiving elements are located on the same uniform bar. The first light-receiving element and the second light-receiving element are input-connected to an operational amplifier so as to apply a signal according to the difference current between the two, and the first light-receiving element and the second light-receiving element are connected as inputs to an operational amplifier so as to apply a signal according to a difference current between the two light-receiving elements. Features: 1- Dimming type smoke detector.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP14141783A JPS6033035A (en) | 1983-08-02 | 1983-08-02 | Light damping type smoke detector |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP14141783A JPS6033035A (en) | 1983-08-02 | 1983-08-02 | Light damping type smoke detector |
Publications (1)
Publication Number | Publication Date |
---|---|
JPS6033035A true JPS6033035A (en) | 1985-02-20 |
Family
ID=15291516
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP14141783A Pending JPS6033035A (en) | 1983-08-02 | 1983-08-02 | Light damping type smoke detector |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPS6033035A (en) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62235547A (en) * | 1986-04-07 | 1987-10-15 | Hochiki Corp | Dimmer type smoke sensor |
JPS63124935A (en) * | 1986-11-14 | 1988-05-28 | Hochiki Corp | Dimming type smoke sensor |
JPS6393547U (en) * | 1986-12-10 | 1988-06-16 | ||
US7659986B2 (en) | 2007-11-15 | 2010-02-09 | Sharp Kabushiki Kaisha | Smoke sensor and electronic equipment |
Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5237791A (en) * | 1975-09-19 | 1977-03-23 | Yoshiaki Ochiai | Mechanism of bilaterally non-symmetrical turning type shelter |
JPS54151399A (en) * | 1978-03-13 | 1979-11-28 | American District Telegraph Co | Warning state detector |
JPS5650446U (en) * | 1979-09-27 | 1981-05-06 | ||
JPS5746593A (en) * | 1980-09-03 | 1982-03-17 | Canon Inc | White balance adjusting device for color video camera |
-
1983
- 1983-08-02 JP JP14141783A patent/JPS6033035A/en active Pending
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5237791A (en) * | 1975-09-19 | 1977-03-23 | Yoshiaki Ochiai | Mechanism of bilaterally non-symmetrical turning type shelter |
JPS54151399A (en) * | 1978-03-13 | 1979-11-28 | American District Telegraph Co | Warning state detector |
JPS5650446U (en) * | 1979-09-27 | 1981-05-06 | ||
JPS5746593A (en) * | 1980-09-03 | 1982-03-17 | Canon Inc | White balance adjusting device for color video camera |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS62235547A (en) * | 1986-04-07 | 1987-10-15 | Hochiki Corp | Dimmer type smoke sensor |
JPS63124935A (en) * | 1986-11-14 | 1988-05-28 | Hochiki Corp | Dimming type smoke sensor |
JPS6393547U (en) * | 1986-12-10 | 1988-06-16 | ||
US7659986B2 (en) | 2007-11-15 | 2010-02-09 | Sharp Kabushiki Kaisha | Smoke sensor and electronic equipment |
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