JPH0368818A - Radio-type liquid-quantity measuring apparatus - Google Patents
Radio-type liquid-quantity measuring apparatusInfo
- Publication number
- JPH0368818A JPH0368818A JP1205403A JP20540389A JPH0368818A JP H0368818 A JPH0368818 A JP H0368818A JP 1205403 A JP1205403 A JP 1205403A JP 20540389 A JP20540389 A JP 20540389A JP H0368818 A JPH0368818 A JP H0368818A
- Authority
- JP
- Japan
- Prior art keywords
- liquid
- temperature
- liquid level
- data
- signal
- 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.)
- Granted
Links
- 239000007788 liquid Substances 0.000 claims abstract description 104
- 238000006243 chemical reaction Methods 0.000 abstract description 8
- 238000013500 data storage Methods 0.000 description 5
- 230000005540 biological transmission Effects 0.000 description 4
- 238000005259 measurement Methods 0.000 description 4
- 238000001514 detection method Methods 0.000 description 3
- 238000010586 diagram Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 1
- 238000004880 explosion Methods 0.000 description 1
- 239000000295 fuel oil Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 238000012806 monitoring device Methods 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は給油所等に埋設されでいる地下タンクの液位を
遠隔地に無線により伝送しで受は側で液量として表示す
る装置に間する。[Detailed Description of the Invention] (Industrial Application Field) The present invention is directed to a device that wirelessly transmits the liquid level in an underground tank buried in a gas station, etc. to a remote location, and displays the liquid level on the receiver side. Pause.
（従来技術）
地下タンクに収容された燃料油等の液量は、通常フロー
ト式液面計により電気信号に変換し、伝送線路でもっで
事務所等のモニタ装置に伝送することにより管理されて
いる。(Prior art) The amount of liquid such as fuel oil stored in an underground tank is usually controlled by converting it into an electrical signal using a float type level gauge and transmitting it to a monitoring device in an office or the like via a transmission line. There is.
（発明か解決しようとする問題点）
しかしなから、地下タンクとモニタ装置との間を伝送線
路で接続する関係上、防爆を考慮した配線上ｉ＋必要と
してコストの引上げを招くという問題がある。(Problems to be Solved by the Invention) However, since the underground tank and the monitor device are connected by a transmission line, there is a problem in that the wiring is required in consideration of explosion protection, leading to an increase in cost.
本発明はこのような問題に鑑みでない九たものであって
、その目的とするところは、配線工事を不要とすること
ができる新規な液量測定装置を提供することにある。The present invention has not been made in view of such problems, and its purpose is to provide a novel liquid level measuring device that can eliminate the need for wiring work.
（問題を解決するための手段）
このような問題を解決１−るために本発明においては、
貯液タンクに設けられて液位データ及び温度データをそ
れぞれ無線周波により伝送する無線式液位信号送信装置
と、該無線式液位信号送信装置からの液位信号及び温度
信号に基づいて液位信号を温度補正し、温度補正済みの
液位信号に基づいて液ｆｆｌを演算するとともに、前記
液量を表示する表示制御装置とを備えた。(Means for solving the problem) In order to solve such problems, the present invention includes the following steps:
A wireless liquid level signal transmitter is installed in the liquid storage tank and transmits liquid level data and temperature data by radio frequency, and the liquid level is determined based on the liquid level signal and temperature signal from the wireless liquid level signal transmitter. The apparatus further includes a display control device that performs temperature correction on the signal, calculates liquid ffl based on the temperature-corrected liquid level signal, and displays the liquid amount.
（作用）
遠隔地点に存在するタンクの液位と、温度を伝送線路を
用いることなく目的地点に伝送させるととも１こ、受信
側で液位を温度補正して液量に変換する。(Function) The liquid level and temperature of a tank located at a remote point are transmitted to the destination point without using a transmission line, and the receiving side corrects the liquid level and converts it into liquid volume.
（実施例）
そこで、以下に本発明の詳細を図示した実施例に基づい
て説明する。(Example) The details of the present invention will be described below based on illustrated examples.
第１図は、本発明を適用した給液設備の一実施例を示す
ものであって、図中符号１は、地下タンク２．２に設け
られる送信装置で、これを構成する厘体内には温度検出
器２２が設けられている。FIG. 1 shows an embodiment of liquid supply equipment to which the present invention is applied, and the reference numeral 1 in the figure is a transmitting device installed in an underground tank 2.2, and inside the reel constituting this, A temperature detector 22 is provided.
３は地下タンクから遠隔地（こある事務所４に設備され
た表示制御装置で、無線周波数の搬送波でもっで地下タ
ンク２．２の液位、及び筐体内の温度を伝送するように
システムが構成されでいる。3 is a display control device installed at a remote location (office 4) from the underground tank, and the system is designed to transmit the liquid level in the underground tank 2.2 and the temperature inside the housing using radio frequency carrier waves. It is already configured.
第２図は、前述した送信装置の一実施例を示すものであ
って、図中符号１０は、マイクロコンピュータからなる
制御手段で、電池１１からの電力を電圧レギュレータ１
２を介して電源端子１０ａに常時受け、また電圧レギュ
レータ１２からの電力を常時受けて作動するタイマー手
段１３からの起動信号を起＠信号入力端子１０ｂに受け
、一定周期、例えば２０秒間隔で間欠的に起動、停止を
繰返すとともに、停止時にはタイマ手段１３からの起動
信号により再起動可能な状態で待機するように構成され
でいる。FIG. 2 shows an embodiment of the above-mentioned transmitting device, and reference numeral 10 in the figure is a control means consisting of a microcomputer, and the power from the battery 11 is transferred to the voltage regulator 1.
The signal input terminal 10b receives a start signal from the timer means 13, which operates by constantly receiving power from the voltage regulator 12, and is activated intermittently at regular intervals, for example, at intervals of 20 seconds. It is configured to repeatedly start and stop, and when stopped, to stand by in a state where it can be restarted by a start signal from the timer means 13.
２０は、液位−温度測定手段で、液位検出用フロートＦ
に連動するポテンショメータ２１と、送信装置の筺体内
の温度、つまりケース内温を検出する第１温度検出器２
２と、タンク内の液温を検出する第２温度検出器２３と
を備えている。20 is a liquid level-temperature measuring means, which includes a liquid level detection float F;
a potentiometer 21 that is linked to the transmitter, and a first temperature detector 2 that detects the temperature inside the housing of the transmitter, that is, the temperature inside the case.
2, and a second temperature detector 23 that detects the temperature of the liquid in the tank.
この測定手段２０は、制御手段１０１こより開閉側ｍを
受ける第１スイツチ１６を介して電力の供給を受ける電
圧レギュレータ２６がら作動電圧の供給を受け、また測
定信号は制御手段１０＋こより切換えられる第２スイツ
チ２５を介して電圧−周波数変換手段２４に出力しでい
る。１７は、変調送信手段で、制御手段１０がらの信号
によりＯＮとなる第３スイツチ１８を介して電圧レギュ
レータ］２から電力の供給を受け、液位−温度測定手段
２０の測定データにより搬送波を変調し、測定データを
無線信号としてアンテナ１９から送出するように構成さ
れでいる。The measuring means 20 is supplied with an operating voltage from a voltage regulator 26 which is supplied with power via a first switch 16 which receives the opening/closing side m from the control means 101, and the measurement signal is supplied to a second switch which is switched from the control means 10+. The signal is output to the voltage-frequency conversion means 24 via the switch 25. Reference numeral 17 denotes a modulation transmitting means, which receives power from the voltage regulator 2 via a third switch 18 which is turned on by a signal from the control means 10, and modulates the carrier wave based on the measurement data of the liquid level-temperature measuring means 20. The antenna 19 is configured to transmit the measurement data as a wireless signal.
次に、このように構成した装置の動作を第３図に示した
フローチャートに基づいて説明する。Next, the operation of the apparatus configured as described above will be explained based on the flowchart shown in FIG.
電池１１からの電力が供給されて装置が作動すると、制
御手段１０はタイマ手段１３がらの起動信号を受は付は
可能な程度の機能を維持したスタンバイ状態となり、ま
たタイマ手段１３は計時動作を開始する（ステップ イ
）。予め設定されでいる時間、例えば２０秒か経過する
と、タイマ手段１３は起＠信号を出力する（スナップ
ロ）。When power is supplied from the battery 11 and the device is activated, the control means 10 receives a start signal from the timer means 13 and enters a standby state in which it maintains a sufficient level of functionality, and the timer means 13 does not perform timekeeping operation. Start (Step I). When a preset time elapses, for example 20 seconds, the timer means 13 outputs a start @ signal (snap).
B).
これにより、制御手段１０は、スタンバイ状態を脱して
起動状態に移り、第１スイツチ１６壱〇Ｎとして液位−
温度構出手段２０に作動電力を供給’する（ステップ
ハ）、液位−温度検出手段２０は、液位に応したポテン
ショメータ２１からの電圧信号ＶＬと、ケース内温に応
じた第１温度検出器２２からの電圧信号Ｖｃと、液体の
温度に応した第２温度検出器２３からの電圧信号Ｖ９、
を出力する。この時点では、第２スイツチ２５によりポ
テンショメータ２１の出力が選択されているので、電圧
信号ＶＬだけが電圧−周波数変換手段２４により周波数
信号に変換されて制御手段１０に出力する（ステップ
ニ）、制御手段１０は、この周波数信号を一定時間カウ
ントする。液位データのサンプリングか終了した段階で
、制御手段１０は、第２スイツチ２５を切換えで（ステ
ップ ホ）、第１温度検出器２２の電圧信号Ｖｃを電圧
−周波数変換手段２４１こ出力ざぜ（ステップ へ）、
ざらに第２スイツチ２５を切換えで（ステップ ト）、
第２温度検出器２３の電圧信号９を電圧−周波数変換手
段２４に出力させる。As a result, the control means 10 exits the standby state and enters the starting state, and the first switch 1610N is turned on to lower the liquid level.
Supplying operating power to the temperature setting means 20 (step
C) The liquid level-temperature detection means 20 receives a voltage signal VL from the potentiometer 21 corresponding to the liquid level, a voltage signal Vc from the first temperature detector 22 corresponding to the case internal temperature, and a voltage signal Vc corresponding to the temperature of the liquid. voltage signal V9 from the second temperature detector 23,
Output. At this point, since the output of the potentiometer 21 is selected by the second switch 25, only the voltage signal VL is converted into a frequency signal by the voltage-frequency conversion means 24 and output to the control means 10 (step
d) The control means 10 counts this frequency signal for a certain period of time. When the sampling of the liquid level data is completed, the control means 10 switches the second switch 25 (Step E) to output the voltage signal Vc of the first temperature detector 22 to the voltage-frequency conversion means 241 (Step E). fart),
Roughly switch the second switch 25 (step),
The voltage signal 9 of the second temperature detector 23 is outputted to the voltage-frequency conversion means 24.
液位データ、気温データ、及び液温データの採取か終了
した時点で（スナップ チ）、制御手段１０は、第１ス
イツチ１６をＯＦＦとして液位−温度検出手段２０への
電力を断ち、また第２スイツチ２５をポテンショメータ
を選択し１．：状態に切換え、次の測定時のデータ出力
順を予め設定しておく０次に、制御手段１０は、第３ス
イツチ１８をＯＮとして変調送信手段１７を作動させ、
取込んでいる液位データ、気温データ、液温デ７りを送
信する（ステップ リ）、全てのデータの送信が終了し
た時点で（ステップ ヌ）、第３スイツチ１８をＯＦＦ
にして変調送信手段１７を停止させ、また制御手段自身
もスタンバイ状態１こ入る（ステップ ル）。When the collection of liquid level data, air temperature data, and liquid temperature data is completed (snap), the control means 10 turns off the first switch 16 to cut off the power to the liquid level-temperature detection means 20, and also turns off the first switch 16. 2 Select the potentiometer with switch 25.1. : state and preset the data output order for the next measurement.Next, the control means 10 turns on the third switch 18 to operate the modulation transmission means 17,
Send the liquid level data, temperature data, and liquid temperature data that has been taken in (Step 1). When all data has been sent (Step 1), turn off the third switch 18.
The modulation transmitting means 17 is stopped, and the control means itself also enters a standby state (step).
以下このような過程を繰返しながらタイマー手段１３に
設定されでいる一定周期で液位、気温、及び液温データ
を送信する。Thereafter, while repeating such a process, the liquid level, air temperature, and liquid temperature data are transmitted at a constant cycle set in the timer means 13.
第４図は、表示制御装置の一実施例を示すものであっＣ
，図中符号４０は、複数のチャンネルを受信する無線受
信手段で、タンク毎に設置されている無線式液位測定装
置からの無線信号を受信するように周波数同調が行われ
ており、また各チャンネルにおいで受信した信号を復調
しＣそれぞれ独立のチャンネルとして出力するように構
成されている。FIG. 4 shows an embodiment of the display control device.
, numeral 40 in the figure is a wireless receiving means for receiving multiple channels, and frequency tuning is performed to receive wireless signals from wireless liquid level measuring devices installed in each tank. It is configured to demodulate the signals received in the channels and output them as independent channels.
４１は、データ記憶手段で、無線受信手段４０からの液
位データ、気温データ、及び液温データを、タンク番号
で割当てられでいるアトし・スのデータ領域に格納する
ものである。Reference numeral 41 denotes a data storage means that stores the liquid level data, air temperature data, and liquid temperature data from the wireless receiving means 40 in the data area assigned by the tank number.
４２は、続出手段で、制御手段４３により指定されたタ
ンク番号に対応するアドレスにアクセスを掛け、ここに
格納されているデータをシリアル−パラレル変換して出
力するものである。Reference numeral 42 denotes a serial output means that accesses the address corresponding to the tank number designated by the control means 43, converts the data stored therein from serial to parallel, and outputs the data.
４４は、変換用データ記憶手段で、液位データのケース
内温の依存特性や、液位と液量との関係、及び基準液温
度にお１する液量への換ｐデータ等を格納して構成され
ている。44 is a data storage means for conversion, which stores the dependence characteristics of the liquid level data on the internal temperature of the case, the relationship between the liquid level and the liquid volume, and the conversion p data to the liquid volume that is equal to the reference liquid temperature. It is composed of
４５．４６は、それぞれ各タンク毎の最高の液量、及び
最低の液ｊｌを格納した最高液量記憶回路と、最低液量
記憶回路である。Reference numerals 45 and 46 denote a maximum liquid volume storage circuit and a minimum liquid volume storage circuit that store the maximum liquid volume and minimum liquid jl for each tank, respectively.
５０は、表示装置で、タンク番号毎に現在の液量を表示
する表示器５１．５２．５３と、タンクの液量が最高、
最低値になったときに警報表示する表示器５４〜５６．
５７〜５９をパネル面に配設しで構成されでいる。50 is a display device that displays the current liquid level for each tank number, and displays 51, 52, and 53 that indicate the maximum liquid level in the tank;
Indicators 54 to 56 that display an alarm when the lowest value is reached.
57 to 59 are arranged on the panel surface.
なお、図中符号６０は表示装Ｍ駆動手段を示す。Note that the reference numeral 60 in the figure indicates a display device M driving means.
次にこのように構成した装置の動作を第５図に示したフ
ローチャートに基づいて説明する。Next, the operation of the apparatus configured as described above will be explained based on the flowchart shown in FIG.
タンク（こ備え付けられた無線式液位測定装置１．１（
第１図）から無線信号が出力されると無線受信手段４０
はこれを受信して（ステップ イ）、データ記憶手段４
１に出力する。データ記憶手段４１は、無線受信手段４
０のチャンネルに対応したアドレスに、今受信した液位
データ、気温データ、及び液温データを格納してデータ
を更新する（ステップ ロ）。Tank (equipped with wireless liquid level measuring device 1.1)
When a wireless signal is output from the wireless receiving means 40 (Fig. 1),
receives this (step I), and the data storage means 4
Output to 1. The data storage means 41 includes the wireless reception means 4
Store the currently received liquid level data, air temperature data, and liquid temperature data in the address corresponding to channel 0 and update the data (step RO).
制御手段４３は、読出手段４２を介して液位記憶手段４
１からタンク毎の液位データ、気温データ、液温データ
を読出し、変換用データ記憶手段４４のデータに基づい
て液位をケース内の気温データにより補正する。これに
より、温度変動により影響ヲ受は易い電圧レギュレータ
２６の出力電圧変化や、ポテンショメータ２１の抵抗値
変化による液位データの温度誤差が取除かれることにな
る６次いて、制御手段４３は、温度補正された液位デー
タを液量に変換し、液量を液温に基づいて補正して基準
温度における液量に換算し、対応する表示器５４〜５６
１こ表示させる（ハ）。同時に最高液量記憶手段４５及
び最低液量記憶手段４６に記憶されている最高液量、最
低液量と比較しくステップ ニ、ホ）、これらに一致す
る場合には最高液量表示器５４〜５６、最低液量表示器
５７−５９を作動させで、液量の過不足をオペレータに
知らせる（ステップ へ、ト）。The control means 43 controls the liquid level storage means 4 via the reading means 42.
1, the liquid level data, air temperature data, and liquid temperature data for each tank are read out, and the liquid level is corrected by the air temperature data in the case based on the data in the conversion data storage means 44. This eliminates temperature errors in the liquid level data due to changes in the output voltage of the voltage regulator 26 and changes in the resistance value of the potentiometer 21, which are easily affected by temperature fluctuations.6 Next, the control means 43 controls the temperature The corrected liquid level data is converted into liquid volume, the liquid volume is corrected based on the liquid temperature and converted to the liquid volume at the reference temperature, and the corresponding indicators 54 to 56
Display one item (c). At the same time, compare the maximum liquid volume and the minimum liquid volume stored in the maximum liquid volume storage means 45 and the minimum liquid volume storage means 46. If they match, the maximum liquid volume indicators 54 to 56 , operate the minimum liquid level indicators 57-59 to notify the operator of excess or insufficient liquid level (to steps 3 and 5).
（発明の効果）
以上、説明したように本発明においでは、貯液タンクに
設けられ゛Ｃ湾位データ及び温度データをそれぞれ無線
周波により伝送する無線式液位信号送信装置と、該無線
式液位信号送信装置からの液位信号及び温度信号に基づ
いて液位信号を温度補正し、温度補正済みの液位信号に
基づいて液量を演算するとともに、前記液量を表示する
表示制御装置とを備えたので、特別な配線工事を必要と
することなく、遠隔地点のタンクの液位と温度を表示装
Ｍ１こ無線伝送して、温度補正が行なわれた正ａな液量
として管理することができる。(Effects of the Invention) As described above, in the present invention, there is provided a wireless liquid level signal transmitting device that is installed in a liquid storage tank and transmits C bay level data and temperature data using radio frequency, and A display control device that temperature-corrects the liquid level signal based on the liquid level signal and temperature signal from the liquid level signal transmission device, calculates the liquid amount based on the temperature-corrected liquid level signal, and displays the liquid amount. With this feature, the liquid level and temperature of a tank at a remote location can be wirelessly transmitted to the display device M1 and managed as a correct liquid level with temperature correction, without the need for special wiring work. I can do it.
第１図は本発明か適用された給液設備の一実施例を示す
図、第２図は本発明の一実施例を示す装置のブロック図
、第３図は同上装置の動作を示すフローチャート、第４
図は同上装置に対応して使用する受信装置の一実施例を
示すブロック図、及び第５図は同上装置の動作を示すフ
ローチャートである。
１・・・・無線式液位温度送信装置
２・・・・地下タンク
３・・・・表示制御装置
１９・・・・アンテナ
２０・・・・液位温度測定手段
２１・・・・ポテンショメータ
２２．２３・・・・温度検出器
Ｆ・・・・フロートFIG. 1 is a diagram showing an embodiment of liquid supply equipment to which the present invention is applied, FIG. 2 is a block diagram of the device showing an embodiment of the present invention, and FIG. 3 is a flowchart showing the operation of the same device. Fourth
The figure is a block diagram showing an embodiment of a receiving device used in correspondence with the above device, and FIG. 5 is a flowchart showing the operation of the same device. 1... Wireless liquid level temperature transmitting device 2... Underground tank 3... Display control device 19... Antenna 20... Liquid level temperature measuring means 21... Potentiometer 22 .23...Temperature detector F...Float
Claims (1)
れぞれ無線周波により伝送する無線式液位信号送信装置
と、該無線式液位信号送信装置からの液位信号及び温度
信号に基づいて液位信号を温度補正し、温度補正済みの
液位信号に基づいて液量を演算するとともに、前記液量
を表示する表示制御装置とを備えた無線式液量測定装置
。A wireless liquid level signal transmitter is installed in the liquid storage tank and transmits liquid level data and temperature data by radio frequency, and the liquid level is determined based on the liquid level signal and temperature signal from the wireless liquid level signal transmitter. A wireless liquid level measuring device comprising: temperature correcting a signal, calculating a liquid level based on a temperature corrected liquid level signal, and displaying the liquid level.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1205403A JP2859312B2 (en) | 1989-08-07 | 1989-08-07 | Wireless liquid meter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1205403A JP2859312B2 (en) | 1989-08-07 | 1989-08-07 | Wireless liquid meter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0368818A true JPH0368818A (en) | 1991-03-25 |
| JP2859312B2 JP2859312B2 (en) | 1999-02-17 |
Family
ID=16506260
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1205403A Expired - Fee Related JP2859312B2 (en) | 1989-08-07 | 1989-08-07 | Wireless liquid meter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2859312B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7113125B2 (en) | 2004-12-16 | 2006-09-26 | International Business Machines Corporation | Method for measuring material level in a container using RFID tags |
| JP2008503744A (en) * | 2004-06-22 | 2008-02-07 | トランセンス テクノロジーズ ピーエルシー | SAW-based tire pressure sensor and valve adapter |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5961717A (en) * | 1982-10-01 | 1984-04-09 | Tokyo Tatsuno Co Ltd | Measurement of liquid volume in tank |
| JPS61205027U (en) * | 1986-06-11 | 1986-12-24 | ||
| JPS63210728A (en) * | 1987-02-27 | 1988-09-01 | Tokyo Tatsuno Co Ltd | Liquid level measuring instrument |
-
1989
- 1989-08-07 JP JP1205403A patent/JP2859312B2/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5961717A (en) * | 1982-10-01 | 1984-04-09 | Tokyo Tatsuno Co Ltd | Measurement of liquid volume in tank |
| JPS61205027U (en) * | 1986-06-11 | 1986-12-24 | ||
| JPS63210728A (en) * | 1987-02-27 | 1988-09-01 | Tokyo Tatsuno Co Ltd | Liquid level measuring instrument |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2008503744A (en) * | 2004-06-22 | 2008-02-07 | トランセンス テクノロジーズ ピーエルシー | SAW-based tire pressure sensor and valve adapter |
| US7113125B2 (en) | 2004-12-16 | 2006-09-26 | International Business Machines Corporation | Method for measuring material level in a container using RFID tags |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2859312B2 (en) | 1999-02-17 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |