JPH0311978Y2 - - Google Patents
Info
- Publication number
- JPH0311978Y2 JPH0311978Y2 JP1983135075U JP13507583U JPH0311978Y2 JP H0311978 Y2 JPH0311978 Y2 JP H0311978Y2 JP 1983135075 U JP1983135075 U JP 1983135075U JP 13507583 U JP13507583 U JP 13507583U JP H0311978 Y2 JPH0311978 Y2 JP H0311978Y2
- Authority
- JP
- Japan
- Prior art keywords
- pulse
- power supply
- terminal device
- signal
- receiver
- 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
- 230000005540 biological transmission Effects 0.000 claims description 11
- 238000001514 detection method Methods 0.000 description 9
- 239000000779 smoke Substances 0.000 description 3
- 238000006243 chemical reaction Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000003287 optical effect Effects 0.000 description 1
- 230000002265 prevention Effects 0.000 description 1
- 238000004904 shortening Methods 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
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- Small-Scale Networks (AREA)
- Dc Digital Transmission (AREA)
Description
【考案の詳細な説明】
本考案は、基底電圧に伝送信号を重畳させてパ
ルス信号の高速伝送を行なう伝送装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a transmission device that performs high-speed transmission of pulse signals by superimposing a transmission signal on a base voltage.
近年においては、端末器からの煙濃度、温度、
ガス濃度等のアナログ検出データを受信機に送出
し、受信機において火災判断を行なうようにした
所謂アナログ火災報知設備の開発が推し進められ
ている。このようなアナログ火災報知設備では、
各端末器にアドレスを設定し、受信機からアドレ
スコードと収集コードで構成される複数ビツトの
パルス信号を一対の電源兼用信号線を介して各端
末器に送出して検出情報の収集を指令すると、各
端末器は自己のアドレスを識別して、アナログ検
出データを複数ビツトのデイジタル信号に変換
し、Ａ／Ｄ変換されたパルス列の検出情報を自己
のアドレスと共に受信機に返送していた。 In recent years, smoke density, temperature,
2. Description of the Related Art Progress is being made in the development of so-called analog fire alarm equipment in which analog detection data such as gas concentration is sent to a receiver, and the receiver makes a fire judgment. In this kind of analog fire alarm equipment,
When an address is set for each terminal device and a multi-bit pulse signal consisting of an address code and a collection code is sent from the receiver to each terminal device via a pair of signal lines that also serve as a power supply, commands are given to collect detection information. , each terminal device identifies its own address, converts analog detection data into a multi-bit digital signal, and returns A/D-converted pulse train detection information to the receiver together with its own address.
ところで、このようなパルス列を用いて情報の
伝送を行なうアナログ火災報知設備では、受信機
に接続される端末器の数が多く、且つ一端末器当
たりの情報量も多いことから、短時間に全ての端
末器から検出情報を収集し、受信機と各端末器と
の信号の伝送を効率的に行なうには、パルス列を
構成する各ビツトパルスのパルス幅およびパルス
間隔を短くして信号を速く伝送することが要求さ
れる。 By the way, in analog fire alarm equipment that transmits information using such pulse trains, there are many terminals connected to the receiver, and the amount of information per terminal is large, so all the information can be transmitted in a short period of time. In order to collect detection information from terminal devices and efficiently transmit signals between the receiver and each terminal device, the pulse width and pulse interval of each bit pulse making up the pulse train are shortened to transmit the signal quickly. This is required.
しかしながら、煙濃度、温度、ガス濃度等のア
ナログ量を検出する端末器は、高インピーダンス
の回路構成を備えており、受信機からのパルス列
の伝送路となる一対の電源兼用信号線に高インピ
ーダンスの端末器が接続されることで、信号線路
間のインピーダンスが高くなる。また、受信機か
らは電源にパルス列の信号を重畳して伝送させる
平行二線の電源兼用信号線が引き出されること
で、信号線路となる一対の電源兼用信号線路間に
微少の線間容量が介在する。 However, terminal devices that detect analog quantities such as smoke concentration, temperature, and gas concentration have a high impedance circuit configuration, and a pair of power supply signal lines that serve as a transmission path for the pulse train from the receiver have high impedance. When the terminal device is connected, the impedance between the signal lines increases. In addition, since two parallel power signal lines are drawn out from the receiver that superimpose pulse train signals on the power source and transmit them, a small amount of line capacitance is created between the pair of power signal lines that serve as signal lines. do.
従つて、受信機から複数のビツトパルスでなる
パルス列のパルス信号が送出されると、端末器側
では各ビツトパルスのパルス電圧が信号線路間に
介在した線間容量に充電される。この線間容量に
充電された充電電荷は、各ビツトパルスの立ち下
がり時に放電する。このとき信号線路間のインピ
ーダンスが高いことで給電時間が長くなると、パ
ルスの立ち下がり時間に遅れを生じ、基底レベル
に達するまでの時間が長くなる。高速伝送を行な
うため、パルス列の各パルス間のパルス間隔を短
くすると、各パルスの立ち下がり時間に遅れを生
じることで立ち下がり時間がパルス間隔より長く
なる。従つて、パルスの立ち下がりが基底レベル
に達するまでに要する時間より次のパルスの立ち
上がりが早くなる。すなわち、パルス波形になま
りを生じ、次のパルスとの判別がしにくくなり、
受信機と端末器の正確な信号伝送が困難になると
いう問題があつた。 Therefore, when a pulse signal of a pulse train consisting of a plurality of bit pulses is sent out from the receiver, the pulse voltage of each bit pulse is charged in the line capacitance interposed between the signal lines on the terminal device side. The charge stored in this line capacitance is discharged at the falling edge of each bit pulse. At this time, if the power supply time becomes longer due to the high impedance between the signal lines, a delay occurs in the fall time of the pulse, and the time required to reach the base level becomes longer. In order to perform high-speed transmission, when the pulse interval between each pulse of a pulse train is shortened, a delay occurs in the fall time of each pulse, so that the fall time becomes longer than the pulse interval. Therefore, the rise of the next pulse is faster than the time required for the fall of the pulse to reach the base level. In other words, the pulse waveform becomes distorted, making it difficult to distinguish it from the next pulse.
There was a problem in that accurate signal transmission between the receiver and the terminal became difficult.
本考案は、上記問題点に鑑みてなされたもの
で、受信機と端末器で、パルス列でなる信号を高
速で且つ、正確に伝送することのできる伝送装置
を提供することを目的とする。 The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a transmission device that can transmit a signal consisting of a pulse train at high speed and accurately between a receiver and a terminal.
この目的を達成するため本考案は、受信機から
引き出された一対の電源兼用信号線間に生じるパ
ルス立ち下がり時の蓄積電荷を受信機に帰還させ
てパルス波形のなまりを除去するようにしたもの
である。 In order to achieve this objective, the present invention removes the rounding of the pulse waveform by returning the accumulated charge at the falling edge of the pulse that occurs between a pair of power supply signal lines led out from the receiver to the receiver. It is.
以下、本考案による伝送装置の一実施例を図面
に基づいて説明する。 Hereinafter, one embodiment of a transmission device according to the present invention will be described based on the drawings.
まず構成を説明すると、１は受信機であり、受
信機１からは一対の電源兼用信号線Ｌ１、および
Ｌ２が引き出され、複数の端末器２ａ，２ｂ，２
ｃ，…２ｎが並列接続される。各端末器２ａ，２
ｂ，２ｃ，…２ｎは、火災による煙濃度、温度、
ガス濃度等のアナログ量を検出する高インピーダ
ンスの回路構成を備えていることで一対の電源兼
用信号線Ｌ１，Ｌ２間は平常時、高インピーダン
スに保たれている。 First, to explain the configuration, 1 is a receiver, and a pair of power signal lines L1 and L2 are drawn out from the receiver 1, and a plurality of terminal devices 2a, 2b, 2
c,...2n are connected in parallel. Each terminal device 2a, 2
b, 2c, ... 2n are the smoke concentration and temperature caused by the fire,
By providing a high impedance circuit configuration for detecting analog quantities such as gas concentration, the impedance between the pair of power supply/signal lines L1 and L2 is maintained at high impedance during normal times.
次に、受信機１の回路構成を説明する。３は重
畳用の重畳電圧、例えば12Vを与える定電圧電源
であり、後で説明するスイツチング動作で基底電
圧に重畳されパルス列のパルス信号を形成する。
４は基底電圧、一例として12Vを与える定電圧電
源であり、端末器２ａ，２ｂ，２ｃ，…２ｎの駆
動用電源を供給する。５は制御部に、例えば5V
の電源を供給する定電圧電源である。制御部は制
御回路６と抵抗Ｒ１，Ｒ２、トランジスタＱ１お
よび発光素子Ｐ１で構成されている。制御回路６
はマイクロコンピユータを組み込み、各端末器２
ａ，２ｂ，２ｃ，…２ｎに対する制御指令、ある
いは検出情報の収集を指令する。すなわち、端末
器２ａ，２ｂ，２ｃ，…２ｎに対するアドレスコ
ードと、情報の収集を指令する収集コードで構成
される指令信号を送出すると共に、受信部７から
の検出情報を入力しており、火災情報を返送した
端末器に対して制御を指令する制御コードを端末
器のアドレスを指定して送出する。制御回路６か
らの収集コードまたは制御コードの指令信号に基
づいてトランジスタＱ１がオン−オフし、発光素
子Ｐ１を間歇的に発光させる。 Next, the circuit configuration of the receiver 1 will be explained. Reference numeral 3 denotes a constant voltage power supply that provides a superimposed voltage, for example 12V, which is superimposed on the base voltage by a switching operation to be described later to form a pulse signal of a pulse train.
Reference numeral 4 denotes a constant voltage power supply that provides a base voltage of, for example, 12V, and supplies power for driving the terminal units 2a, 2b, 2c, . . . 2n. 5 is for the control unit, for example 5V
It is a constant voltage power supply that supplies power. The control section includes a control circuit 6, resistors R1 and R2, a transistor Q1, and a light emitting element P1. Control circuit 6
incorporates a microcomputer, and each terminal 2
A, 2b, 2c, . . . 2n are given control commands or collection of detection information is given. That is, it sends out a command signal consisting of an address code for the terminals 2a, 2b, 2c, ... 2n and a collection code that instructs information collection, and also inputs detection information from the receiving section 7. A control code that commands control to the terminal device that sent back the information is sent by specifying the address of the terminal device. The transistor Q1 is turned on and off based on the command signal of the collection code or control code from the control circuit 6, causing the light emitting element P1 to emit light intermittently.
一方、定電圧電源３の負端子と定電圧電源４の
正端子とを接続して同電位に短絡しており、定電
圧電源３の電源端子間には抵抗Ｒ８と、発光素子
Ｐ１からの発射光を受光する受光素子Ｐ２と、受
光素子Ｐ２の導通で反転出力を与えるインバータ
８とで変換回路を形成し、制御部の発光素子Ｐ１
からの間歇的な発光による光学的指令信号を電気
的指令信号に変換する。抵抗Ｒ３およびＲ４とト
ランジスタＱ２およびダイオードＤ１で重畳回路
を形成し、変換回路からの指令信号に基づいてト
ランジスタＱ２をスイツチング動作させ定電圧電
源３からの重畳電圧を定電圧電源４の基底電圧に
重畳してパルス列のパルス信号を送出する。 On the other hand, the negative terminal of the constant voltage power supply 3 and the positive terminal of the constant voltage power supply 4 are connected and short-circuited to the same potential, and a resistor R8 is connected between the power supply terminals of the constant voltage power supply 3, and a A conversion circuit is formed by a light-receiving element P2 that receives light and an inverter 8 that provides an inverted output when the light-receiving element P2 is conductive.
The optical command signal generated by the intermittent light emission from the sensor is converted into an electrical command signal. A superimposition circuit is formed by resistors R3 and R4, transistor Q2, and diode D1, and transistor Q2 is operated to switch based on the command signal from the conversion circuit to superimpose the superimposed voltage from constant voltage power supply 3 on the base voltage of constant voltage power supply 4. and sends out a pulse train of pulse signals.
抵抗Ｒ５，Ｒ６およびトランジスタＱ３は帰還
回路であり、端末器に対するパルス列のパルス伝
送でパルスのあき時間に一対の電源兼用信号線Ｌ
１，Ｌ２間に生じる蓄積電荷を定電圧電源４に帰
還させて、パルス間の蓄積電荷を除去する。Ｄ２
は逆流防止用のダイオード、Ｒ７は端末器２ａ，
２ｂ，２ｃ，…２ｎからの電流モードによる返送
信号を検出する電流検出用の抵抗であり、抵抗Ｒ
７の両端から受信部７に接続している。受信部７
はマイクロコンピユータを組み込んだ信号処理部
を備えており、各端末器２ａ，２ｂ，２ｃ，…２
ｎからの電流モードによる返送信号を電圧モード
に変換して受信し、各端末器２ａ，２ｂ，２ｃ，
…２ｎのアドレスを識別して端末器毎に検出情報
を判別する。情報内容が火災情報であることを判
別すると、火災警報を行なうと共に、火災情報を
返送した端末器のアドレスと情報内容を制御回路
６に送出する。 Resistors R5, R6 and transistor Q3 are a feedback circuit, and during pulse transmission of a pulse train to the terminal device, a pair of power supply signal line L is connected during pulse idle time.
The accumulated charge generated between pulses 1 and L2 is fed back to the constant voltage power supply 4, and the accumulated charge between pulses is removed. D2
is a diode for backflow prevention, R7 is the terminal device 2a,
This is a current detection resistor that detects the return signal in current mode from 2b, 2c, ...2n, and the resistor R
7 is connected to the receiving section 7 from both ends. Receiving section 7
is equipped with a signal processing section incorporating a microcomputer, and each terminal device 2a, 2b, 2c,...2
The return signal in current mode from n is converted into voltage mode and received, and each terminal device 2a, 2b, 2c,
...2n addresses are identified and detection information is determined for each terminal device. When it is determined that the information content is fire information, a fire alarm is issued and the address and information content of the terminal device that returned the fire information is sent to the control circuit 6.
次に、動作を説明する。制御部からの間歇的な
発光出力に基づいて受光素子Ｐ２が動作し、トラ
ンジスタＱ２をスイツチング動作させる。トラン
ジスタＱ２のスイツチング動作でダイオードＤ１
を介して定電圧電源３から重畳電圧12Vが定電圧
電源４からの基底電圧12Vに重畳され、パルス列
のパルス信号を端末器２に伝送する。このときの
パルスのあき時間、すなわちトランジスタＱ２の
オフ時間では、端末器２が高インピーダンスであ
り、且つ一対の電源兼用信号線Ｌ１，Ｌ２間に線
間容量が介在することでパルスの立ち下がり時に
電荷が蓄積し、一対の電源兼用信号線Ｌ１，Ｌ２
間の電圧は定電圧電源４の基底電圧12Vより蓄積
電荷分だけ高くなる。従つて、トランジスタＱ３
のコレクタに対しエミツタ側の電圧が高くなるこ
とで、トランジスタＱ３が導通して一対の電源兼
用信号線Ｌ１，Ｌ２間に生じたパルス立ち下がり
時の蓄積電荷をトランジスタＱ３を通じて定電圧
電源４に帰還させる。パルスのあき時間に生じた
蓄積電荷を定電圧電源４に帰還させることで端末
器２の入力端子には方形のパルスでなるパルス列
のパルス信号が入力する。 Next, the operation will be explained. The light receiving element P2 operates based on the intermittent light emission output from the control section, causing the transistor Q2 to perform a switching operation. Due to the switching operation of transistor Q2, diode D1
A superimposed voltage of 12 V from the constant voltage power source 3 is superimposed on the base voltage of 12 V from the constant voltage power source 4 via the constant voltage power source 4, and a pulse train of pulse signals is transmitted to the terminal device 2. At this time, during the idle time of the pulse, that is, the off time of the transistor Q2, the terminal device 2 has a high impedance, and there is a line capacitance between the pair of power signal lines L1 and L2, so that at the falling edge of the pulse Charge accumulates, and a pair of power signal lines L1 and L2
The voltage between them is higher than the base voltage of 12V of the constant voltage power supply 4 by the amount of accumulated charge. Therefore, transistor Q3
As the voltage on the emitter side becomes higher with respect to the collector of the transistor Q3, the transistor Q3 becomes conductive and the accumulated charge at the falling edge of the pulse generated between the pair of power supply/signal lines L1 and L2 is returned to the constant voltage power supply 4 through the transistor Q3. let By feeding back the accumulated charges generated during the pulse idle time to the constant voltage power supply 4, a pulse signal of a pulse train consisting of square pulses is input to the input terminal of the terminal device 2.
尚、図面ではトランジスタＱ２をNPN、トラ
ンジスタＱ３をPNPとして構成したが、トラン
ジスタＱ２をPNP、トランジスタＱ３をNPNの
トランジスタを用いて構成してもよい。 In the drawings, the transistor Q2 is configured as an NPN and the transistor Q3 is configured as a PNP, but the transistor Q2 may be configured as a PNP and the transistor Q3 may be configured as an NPN transistor.
また、基底電源４からの基底電圧の出力部にツエ
ナダイオードやトランジスタ等を用いてなまり電
圧を消費させる消費回路を設けると、端末器２に
入力するパルス列のパルスがより急峻に立ち下が
り、パルス信号の判別性が更に向上する。Furthermore, if a consumption circuit that consumes the rounded voltage using a Zener diode, a transistor, etc. is provided in the output section of the base voltage from the base power supply 4, the pulses of the pulse train input to the terminal device 2 fall more steeply, and the pulse signal The discriminability of is further improved.
以上、説明してきたように、本考案によれば受
信機からのパルス列でなるパルス信号を基底電圧
に重畳させて一対の電源兼用信号線を介して伝送
する伝送装置において、パルスのあき時間に、一
対の電源兼用信号線間に生じる蓄積電荷を基底電
圧を与える定電圧電源に帰還させるようにしたこ
とでパルス列のパルスの立ち下がりが急峻になつ
て各パルスの識別性が高まり、パルス間隔を短く
したパルス列のパルス信号を送出して多量の情報
を高速、且つ正確に伝送することができるという
効果が得られる。 As explained above, according to the present invention, in a transmission device that superimposes a pulse signal consisting of a pulse train from a receiver on a base voltage and transmits it via a pair of power supply signal lines, By feeding back the accumulated charge generated between a pair of power and signal lines to the constant voltage power supply that provides the base voltage, the pulses in the pulse train fall more steeply, making each pulse more distinguishable and shortening the pulse interval. The effect is that a large amount of information can be transmitted at high speed and accurately by sending out a pulse signal of a pulse train.
図は、本考案の一実施例を示す回路図である。
１：受信機、２ａ，２ｂ，２ｃ，…２ｎ：端末
器、３，４，５：定電圧電源、６：制御回路、
７：受信部、Ｌ１，Ｌ２：電源兼用信号線、Ｑ
１，Ｑ２，Ｑ３：トランジスタ、Ｒ１〜Ｒ８：抵
抗、Ｐ１：発光素子、Ｐ２：受光素子、Ｄ１，Ｄ
２：ダイオード、８：インバータ。
The figure is a circuit diagram showing an embodiment of the present invention. 1: Receiver, 2a, 2b, 2c, ... 2n: Terminal, 3, 4, 5: Constant voltage power supply, 6: Control circuit,
7: Receiving section, L1, L2: Power supply signal line, Q
1, Q2, Q3: transistor, R1 to R8: resistor, P1: light emitting element, P2: light receiving element, D1, D
2: Diode, 8: Inverter.
Claims (1)
に端末器を接続して、重畳電源からの重畳電圧を
制御部からの制御信号に基づいたスイツチング動
作で基底電源からの基底電圧に重畳させて前記端
末器にパルス信号を伝送する伝送装置において、 前記受信機に、前記制御信号に基づくパルス信
号の立ち下がりのタイミングと同時にスイツチン
グして前記一対の電源兼用信号線間に蓄積された
電荷を前記規定電源に帰還させる帰還回路を設け
たことを特徴とする伝送装置。[Claim for Utility Model Registration] A terminal device is connected to a pair of power supply signal lines drawn out from the receiver, and the superimposed voltage from the superimposed power supply is switched from the base power supply by a switching operation based on a control signal from the control unit. In the transmission device that transmits a pulse signal to the terminal device by superimposing it on a base voltage of A transmission device characterized in that a feedback circuit is provided for feeding back charges accumulated in the power source to the specified power source.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13507583U JPS6043052U (en) | 1983-08-31 | 1983-08-31 | transmission device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP13507583U JPS6043052U (en) | 1983-08-31 | 1983-08-31 | transmission device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6043052U JPS6043052U (en) | 1985-03-26 |
| JPH0311978Y2 true JPH0311978Y2 (en) | 1991-03-22 |
Family
ID=30304146
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP13507583U Granted JPS6043052U (en) | 1983-08-31 | 1983-08-31 | transmission device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6043052U (en) |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9010470B2 (en) | 2009-10-09 | 2015-04-21 | Invacare Corporation | Wheelchair suspension |
| US9149398B2 (en) | 2000-10-27 | 2015-10-06 | Invacare Corporation | Obstacle traversing wheelchair |
| US9308143B2 (en) | 2012-02-15 | 2016-04-12 | Invacare Corporation | Wheelchair suspension |
| US9346335B2 (en) | 2007-02-14 | 2016-05-24 | Invacare Corporation | Stability control system |
| US9364377B2 (en) | 2002-10-25 | 2016-06-14 | Invacare Corporation | Suspension for wheeled vehicles |
| US9370455B2 (en) | 2001-10-10 | 2016-06-21 | Invacare Corporation | Wheelchair suspension |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5833739A (en) * | 1981-08-21 | 1983-02-28 | Toshiba Corp | Bus line driving circuit |
-
1983
- 1983-08-31 JP JP13507583U patent/JPS6043052U/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5833739A (en) * | 1981-08-21 | 1983-02-28 | Toshiba Corp | Bus line driving circuit |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US9149398B2 (en) | 2000-10-27 | 2015-10-06 | Invacare Corporation | Obstacle traversing wheelchair |
| US9370455B2 (en) | 2001-10-10 | 2016-06-21 | Invacare Corporation | Wheelchair suspension |
| US9364377B2 (en) | 2002-10-25 | 2016-06-14 | Invacare Corporation | Suspension for wheeled vehicles |
| US9346335B2 (en) | 2007-02-14 | 2016-05-24 | Invacare Corporation | Stability control system |
| US11850906B2 (en) | 2007-02-14 | 2023-12-26 | Invacare Corporation | Stability control system |
| US9010470B2 (en) | 2009-10-09 | 2015-04-21 | Invacare Corporation | Wheelchair suspension |
| US9913768B2 (en) | 2009-10-09 | 2018-03-13 | Invacare Corporation | Wheelchair suspension |
| US9308143B2 (en) | 2012-02-15 | 2016-04-12 | Invacare Corporation | Wheelchair suspension |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS6043052U (en) | 1985-03-26 |
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