JPS6337338B2 - - Google Patents
Info
- Publication number
- JPS6337338B2 JPS6337338B2 JP55002730A JP273080A JPS6337338B2 JP S6337338 B2 JPS6337338 B2 JP S6337338B2 JP 55002730 A JP55002730 A JP 55002730A JP 273080 A JP273080 A JP 273080A JP S6337338 B2 JPS6337338 B2 JP S6337338B2
- Authority
- JP
- Japan
- Prior art keywords
- circuit
- oscillation
- output
- sampling
- smoke
- 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
Links
Classifications
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING SYSTEMS, e.g. PERSONAL CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B17/00—Fire alarms; Alarms responsive to explosion
- G08B17/10—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means
- G08B17/103—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using a light emitting and receiving device
- G08B17/107—Actuation by presence of smoke or gases, e.g. automatic alarm devices for analysing flowing fluid materials by the use of optical means using a light emitting and receiving device for detecting light-scattering due to smoke
Landscapes
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Business, Economics & Management (AREA)
- Emergency Management (AREA)
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Investigating Or Analysing Materials By Optical Means (AREA)
- Fire-Detection Mechanisms (AREA)
Description
【発明の詳細な説明】
この発明は光電式煙感知器に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photoelectric smoke detector.
従来の光電式煙感知器は、消費電流を減らすた
めに発光素子の発光周期が通常数秒から10秒程度
とかなり長く設定されており、また、外来ノイ
ズ、フラツシユ等による外乱光等による誤報を防
止するために発光時に連続して数周期間煙が存在
しないと動作しないように構成されている。この
ため、従来は、あるレベル以上の煙が存在して光
電式煙感知器が動作するまでに10秒〜数10秒間必
要とするので、動作テスト時には、動作するまで
煙を入れつづける必要があり、動作する段階では
光電式煙感知器内にかなり濃い煙が存在すること
になる。このことは、光電式煙感知器が復旧する
までに時間がかなりかかるという問題となつて現
れた。また、実際に火災が発生した場合にも煙感
知に要する時間が長くなるという欠点があつた。 In conventional photoelectric smoke detectors, the light emitting cycle of the light emitting element is set to be quite long, usually from several seconds to about 10 seconds, in order to reduce current consumption, and this also prevents false alarms due to external noise, ambient light caused by flashes, etc. In order to do this, the device is configured so that it will not operate unless smoke is present for several consecutive cycles when emitting light. For this reason, conventionally, it takes 10 to several tens of seconds for a photoelectric smoke detector to activate when there is smoke above a certain level, so when testing the operation, it is necessary to keep introducing smoke until it activates. , there will be quite a thick smoke inside the photoelectric smoke detector during the operating stage. This has resulted in the problem that it takes a considerable amount of time for photoelectric smoke detectors to recover. Another disadvantage is that it takes a long time to detect smoke even when a fire actually occurs.
したがつて、この発明の目的は、消費電流を増
加させることなく、誤報を防止し、しかも煙感知
に要する時間を短くできる光電式煙感知器を提供
することである。 Therefore, an object of the present invention is to provide a photoelectric smoke detector that can prevent false alarms and shorten the time required for smoke detection without increasing current consumption.
この発明の一実施例を第１図および第２図に示
す。すなわち、この光電式煙感知器は、第１図に
示すように、発振周期を連続的に変化可能な可変
周期パルス発振回路１と、この可変周期パルス発
振回路１より給電されて間欠発光する発光素子２
と、この発光素子２の光の煙粒子による散乱光を
受光する受光素子３と、この受光素子３の出力を
増幅する増幅器４と、この増幅器４の出力を可変
周期パルス発振回路１の発振パルスに応答してサ
ンプリング・ホールドしそのサンプリング・ホー
ルド値の大小に応じて可変周期パルス発振回路１
の発振周期を短長に変化させるサンプリング・ホ
ールド回路５と、このサンプリング・ホールド回
路５の一定値以上の出力を発振パルスに応答して
連続的に一定数（３個）計数したときに煙感知出
力を発生する計数回路６と、この計数回路６の煙
感知出力に応答してオンとなるスイツチ回路７
と、このスイツチ回路７のオンに応答して鳴動す
るブザー８とを備えている。この場合、可変周期
パルス発振回路（電圧−周波数変換回路）１は、
第２図に示すように、演算増幅器OP1、抵抗R1〜
R3およびコンデンサC1よりなりサンプリング・
ホールド回路５のサンプリング・ホールド値を積
分する積分回路と、抵抗R4，R5および演算増幅
器OP2よりなり積分回路の積分値に応じて状態を
反転するシユミツト回路と、抵抗R6およびスイ
ツチSW1よりなりシユミツト回路の発振パルスに
応答してコンデンサC1の電荷を放電する放電回
路とから構成されている。また、サンプリング・
ホールド回路５は、コンデンサC2，C3、抵抗R7，
R8およびスイツチSW2より構成され、可変周期
パルス発振回路１のパルス発生期間中スイツチ
SW2がオンとなつて増幅器４の出力をサンプリン
グしてパルス休止期間中スイツチSW2がオフとな
つてその値をホールドするようになつている。さ
らに、計数回路６は、比較器CP、抵抗R9，R10、
ＤフリツプフロツプFF1，FF2，FF3およびアン
ド回路G1，G2より構成され、サンプリング・ホ
ールド回路５の出力値を比較器CPで一定値と比
較し、一定値を越えるとその回数がＤフリツプフ
ロツプFF1，FF2，FF3よりなるシフトレジスタ
により発光と同期して計数され、一定値を越える
出力が３回連続して出現するとアンド回路G2よ
り出力が発生するようになつている。 An embodiment of the invention is shown in FIGS. 1 and 2. That is, as shown in FIG. 1, this photoelectric smoke detector includes a variable period pulse oscillation circuit 1 whose oscillation period can be changed continuously, and a light emitting device that is powered by the variable period pulse oscillation circuit 1 and emits light intermittently. Element 2
, a light receiving element 3 that receives the light scattered by the smoke particles of the light emitting element 2 , an amplifier 4 that amplifies the output of the light receiving element 3 , and an oscillation pulse of the variable period pulse oscillation circuit 1 that converts the output of the amplifier 4 into an oscillation pulse. The variable period pulse oscillation circuit 1 performs sampling and holding in response to the sampling and holding value.
A sampling/holding circuit 5 that shortens the oscillation period of the sampling/holding circuit 5, and smoke detection is detected when a certain number (3) of outputs of the sampling/holding circuit 5 are continuously counted over a certain value in response to an oscillation pulse. A counting circuit 6 that generates an output, and a switch circuit 7 that is turned on in response to the smoke detection output of this counting circuit 6.
and a buzzer 8 that sounds in response to turning on the switch circuit 7. In this case, the variable period pulse oscillation circuit (voltage-frequency conversion circuit) 1 is
As shown in Fig. 2, operational amplifier OP 1 and resistor R 1 ~
The sampling circuit consists of R 3 and capacitor C 1 .
An integrator circuit that integrates the sampling and hold value of the hold circuit 5, a Schmitt circuit that is made up of resistors R 4 and R 5 and an operational amplifier OP 2 and inverts the state according to the integrated value of the integrator circuit, and a resistor R 6 and a switch SW. 1 and a discharge circuit that discharges the charge of the capacitor C1 in response to the oscillation pulse of the Schmitt circuit. Also, sampling
The hold circuit 5 includes capacitors C 2 , C 3 , resistors R 7 ,
Consisting of R 8 and switch SW 2 , the switch is activated during the pulse generation period of variable period pulse oscillation circuit 1.
SW 2 is turned on to sample the output of the amplifier 4, and during the pulse pause period, switch SW 2 is turned off to hold that value. Furthermore, the counting circuit 6 includes a comparator CP, resistors R 9 , R 10 ,
Consisting of D flip-flops FF 1 , FF 2 , FF 3 and AND circuits G 1 , G 2 , the output value of the sampling/holding circuit 5 is compared with a constant value by a comparator CP, and if it exceeds the constant value, the number of times is D A shift register consisting of flip-flops FF 1 , FF 2 , and FF 3 performs counting in synchronization with the light emission, and when an output exceeding a certain value appears three times in a row, an output is generated from an AND circuit G 2 .
なお、９は電圧VDDの直流電源、１０は発光素
子駆動用トランジスタ、１１は限流抵抗、１２は
バツフアである。 Note that 9 is a DC power source with a voltage of VDD , 10 is a transistor for driving a light emitting element, 11 is a current limiting resistor, and 12 is a buffer.
第３図は、この実施例における煙濃度Ａと、可
変周期パルス発振回路１の出力Ｂと、スイツチン
グ回路７の出力Ｃとを示している。すなわち、煙
濃度が第３図Ａのように、時間の経過とともに高
くなつて一定値L1を越え、その後一定値L1より
低くなるというような変化をした場合、可変周期
パルス発振回路１の発振周期は、第３図Ｂに示す
ように、煙濃度の増加（サンプリング・ホールド
値の増加）とともにT1，T2，T3と順次短くな
り、煙濃度の減少とともに発振周期が長くなる。
一方、スイツチング回路７は、第３図Ｃに示すよ
うに、可変周期パルス発振回路１の出力パルスが
３回連続する期間煙濃度が一定値L1を越えると
オンとなり、ブザー８を鳴動させる。 FIG. 3 shows the smoke density A, the output B of the variable period pulse oscillation circuit 1, and the output C of the switching circuit 7 in this embodiment. That is, when the smoke density increases over time and exceeds a constant value L1 , and then decreases below the constant value L1 , as shown in FIG. 3A, the variable period pulse oscillation circuit 1 As shown in FIG. 3B, the oscillation period becomes shorter as the smoke concentration increases (as the sampling hold value increases), T 1 , T 2 , and T 3 , and as the smoke concentration decreases, the oscillation period becomes longer.
On the other hand, as shown in FIG. 3C, the switching circuit 7 is turned on and causes the buzzer 8 to sound when the smoke density exceeds a certain value L1 during three consecutive output pulses from the variable period pulse oscillation circuit 1 .
なお、この実施例では、計数回路６がサンプリ
ング・ホールド回路５の一定値以上の出力を発振
パルスに応答して連続的に３回計数したときに煙
感知出力を発生するように構成したが、回数は２
回でも４回以上でもよい。 In this embodiment, the smoke detection output is generated when the counting circuit 6 successively counts the output of the sampling/holding circuit 5 equal to or higher than a certain value three times in response to the oscillation pulse. The number of times is 2
It may be twice or more than four times.
以上のように、この発明の光電式煙感知器は、
サンプリング・ホールド回路のサンプリング・ホ
ールド値の大小すなわち煙の濃淡に応じて可変周
期パルス発振回路の発振周期を短長に変化させ、
サンプリング・ホールド回路の一定値以上の出力
を発振パルスに応答して連続的に一定数計数した
ときに計数回路が煙感知出力を発生するようにし
たため、消費電流の増加を押さえ、誤動作を防止
して、煙感知に要する時間を少くでき、その結
果、動作テスト時の器内の煙濃度を低く押えるこ
とができ、したがつて、その後の復旧時間を短く
でき、また実際の火災もいちはやく感知できると
いう効果がある。また、この光電式煙感知器は、
可変周期パルス発振回路を用い、サンプリング・
ホールド回路（受光素子の出力を増幅する増幅器
の出力をサンプリング・ホールドする）の出力レ
ベルに応じて発光素子から出力される光パルスの
周期を変化させるようにしているため、煙の濃度
が高くなればなるほど煙感知を早く行うことがで
きるという利点がある。 As described above, the photoelectric smoke detector of this invention is
The oscillation period of the variable period pulse oscillation circuit is changed to short or long according to the magnitude of the sampling and hold value of the sampling and holding circuit, that is, the density of smoke,
The counting circuit generates a smoke detection output when the output of the sampling/holding circuit exceeds a certain value and continuously counts a certain number of times in response to an oscillation pulse, which suppresses the increase in current consumption and prevents malfunctions. As a result, the time required for smoke detection can be reduced, and as a result, the smoke concentration inside the device can be kept low during operation tests, and subsequent recovery time can be shortened, and an actual fire can be detected quickly. There is an effect. In addition, this photoelectric smoke detector
Sampling and
Because the period of the light pulse output from the light emitting element is changed according to the output level of the hold circuit (which samples and holds the output of the amplifier that amplifies the output of the light receiving element), the smoke density increases. The advantage is that smoke detection can be performed more quickly.
第１図はこの発明の一実施例の光電式煙感知器
のブロツク図、第２図はその具体回路図、第３図
はその動作を説明するための波形図である。
１……可変周期パルス発振回路、２……発光素
子、３……受光素子、４……増幅器、５……サン
プリング・ホールド回路、６……計数回路、７…
…スイツチング回路、８……ブザー。
FIG. 1 is a block diagram of a photoelectric smoke detector according to an embodiment of the present invention, FIG. 2 is a specific circuit diagram thereof, and FIG. 3 is a waveform diagram for explaining its operation. DESCRIPTION OF SYMBOLS 1... Variable period pulse oscillation circuit, 2... Light emitting element, 3... Light receiving element, 4... Amplifier, 5... Sampling/hold circuit, 6... Counting circuit, 7...
...Switching circuit, 8...Buzzer.
Claims (1)
ス発振回路と、この可変周期パルス発振回路より
給電されて間欠発光する発光素子と、この発光素
子の光の煙粒子による散乱光を受光する受光素子
と、この受光素子の出力を増幅する増幅器と、こ
の増幅器の出力を前記可変周期パルス発振回路の
発振パルスに応答してサンプリング・ホールドし
そのサンプリング・ホールド値の大小に応じて前
記可変周期パルス発振回路の発振周期を短長に変
化させるサンプリング・ホールド回路と、このサ
ンプリング・ホールド回路の一定値以上の出力を
前記発振パルスに応答して連続的に一定数計数し
たときに煙感知出力を発生する計数回路と、この
計数回路の煙感知出力に応答してオンとなるスイ
ツチ回路と、このスイツチ回路のオンに応答して
鳴動するブザーとを備えた光電式煙感知器。1. A variable period pulse oscillation circuit whose oscillation period can be changed continuously, a light emitting element that is powered by the variable period pulse oscillation circuit and emits light intermittently, and a light receiving element that receives light scattered by smoke particles from the light emitting element. an amplifier that amplifies the output of the light receiving element; and an amplifier that samples and holds the output of the amplifier in response to the oscillation pulse of the variable period pulse oscillation circuit, and generates the variable period pulse oscillation according to the magnitude of the sampling and hold value. A sampling and holding circuit that changes the oscillation period of the circuit to a shorter length, and a smoke detection output is generated when the output of this sampling and holding circuit that exceeds a certain value is continuously counted a certain number of times in response to the oscillation pulse. A photoelectric smoke detector comprising a counting circuit, a switch circuit that is turned on in response to the smoke detection output of the counting circuit, and a buzzer that sounds in response to the turning on of the switch circuit.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP273080A JPS56100343A (en) | 1980-01-14 | 1980-01-14 | Photoelectric type smoke sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP273080A JPS56100343A (en) | 1980-01-14 | 1980-01-14 | Photoelectric type smoke sensor |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56100343A JPS56100343A (en) | 1981-08-12 |
| JPS6337338B2 true JPS6337338B2 (en) | 1988-07-25 |
Family
ID=11537427
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP273080A Granted JPS56100343A (en) | 1980-01-14 | 1980-01-14 | Photoelectric type smoke sensor |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56100343A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6053047U (en) * | 1983-09-20 | 1985-04-13 | ホーチキ株式会社 | Smoke detectors |
| JPH05166080A (en) * | 1991-12-16 | 1993-07-02 | Yamato Protec Co | Fire alarm |
| JP4996380B2 (en) * | 2007-07-13 | 2012-08-08 | 矢崎総業株式会社 | Fire alarm |
| WO2013146244A1 (en) * | 2012-03-27 | 2013-10-03 | テルモ株式会社 | Sensing device and sensing method |
| JP6109812B2 (en) * | 2012-03-27 | 2017-04-05 | テルモ株式会社 | Sensing device |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS59878B2 (en) * | 1975-09-04 | 1984-01-09 | 松下電工株式会社 | sensor |
| IL52977A (en) * | 1976-11-16 | 1979-09-30 | Chloride Batterijen Bv | Smoke detector |
| JPS53143287A (en) * | 1977-05-19 | 1978-12-13 | Nittan Co Ltd | Photoelectric smoke detector |
-
1980
- 1980-01-14 JP JP273080A patent/JPS56100343A/en active Granted
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56100343A (en) | 1981-08-12 |
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