JP2766060B2 - Water supply device - Google Patents
Water supply deviceInfo
- Publication number
- JP2766060B2 JP2766060B2 JP2242324A JP24232490A JP2766060B2 JP 2766060 B2 JP2766060 B2 JP 2766060B2 JP 2242324 A JP2242324 A JP 2242324A JP 24232490 A JP24232490 A JP 24232490A JP 2766060 B2 JP2766060 B2 JP 2766060B2
- Authority
- JP
- Japan
- Prior art keywords
- pump
- current
- water supply
- electric motor
- supply device
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、電動ポンプと圧力タンクを備えた給水装置
に係り、特に落水による無水運転や、ポンプ異常その他
の原因による電動機の過負荷運転を防止するシステムに
好適な給水装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a water supply device provided with an electric pump and a pressure tank, and particularly to an anhydrous operation due to falling water and an overload operation of an electric motor due to a pump abnormality or other causes. The present invention relates to a water supply device suitable for a prevention system.
従来より電動機の運転電流により、ポンプの無水運転
や過負荷を検知することは行われている。この種の装置
として、実開昭52−98202号がある。この装置は接点付
き電流計により一定時間、低運転電流が続いたとき無水
運転と見なし、電動機を停止させるものである。2. Description of the Related Art Conventionally, detection of anhydrous operation and overload of a pump based on an operating current of a motor has been performed. As this type of apparatus, there is Japanese Utility Model Laid-Open No. 52-98202. In this device, when a low operating current continues for a certain period of time by an ammeter with contacts, it is regarded as anhydrous operation and the motor is stopped.
上記従来技術は落水時に電動機を停止することを目的
としており、落水そのものの防止や、落水からの回復に
ついて配慮がなされていない。The above-mentioned prior art aims to stop the electric motor at the time of water fall, and does not consider prevention of water fall itself or recovery from water fall.
本発明は２台以上のポンプを有する給水装置の落水防
止を目的としている。An object of the present invention is to prevent a water supply device having two or more pumps from falling.
上記目的を達成するため、本発明は、２台以上のポン
プと、これを駆動する電動機と、ポンプ吐出側にある圧
力タンクと、給水管と、これに備わる圧力センサーを有
し、前記圧力センサーの信号を基に、給水量の変動に応
じて、前記ポンプをある定められた順序に従って運転す
る給水装置において、前記電動機の電流を検出する電流
検出手段と、ポンプ内への空気混入による負荷低下を予
測して予め決めた電動機の運転下限電流値を設定する手
段と、空気混入による落水が起こると予想される時間を
超えない範囲で予め決めた許容運転時間を設定する手段
と、前記電流検出手段により検出された電流値が運転下
限電流値以下になったことを検知する手段と、該検知さ
れている時間が連続して前記許容運転時間以上続いたこ
とを判定する手段と、該手段により前記許容運転時間以
上続いたと判定されたら当該電動機で駆動されているポ
ンプを停止させ休止中の他のポンプを運転させる手段を
備えるように構成したものである。In order to achieve the above object, the present invention has two or more pumps, an electric motor for driving the pumps, a pressure tank on a pump discharge side, a water supply pipe, and a pressure sensor provided therewith. A water detecting device for detecting the current of the electric motor in a water supply device that operates the pump in accordance with a predetermined order according to a change in water supply amount based on the signal of Means for setting a predetermined operating lower limit current value of the electric motor by predicting the electric current, means for setting a predetermined allowable operation time within a time period not expected to cause water drop due to air mixing, and Means for detecting that the current value detected by the means has become equal to or less than the operation lower limit current value, and means for determining that the time during which the current has been detected has continued for the allowable operation time or more. Is obtained by configured with means for driving the other pump in the allowable operating time or lasted as to stop the pump, which is driven in the motor when it is judged rest by said means.
制御装置は運転電流を常に監視し、予め設定された電
動機の運転下限電流値（ポンプ内への空気混入による負
荷低下を予測して設定）以下の電流が一定時間（空気混
入による落水が起こると予想される時間を超えない範囲
で予め決めた許容運転時間）以上続いたときは当該電動
機で駆動されるポンプを停止させ、休止中の他のポンプ
を運転させる。The control device constantly monitors the operating current, and a current equal to or less than a predetermined operating lower limit current value of the electric motor (set by predicting a load decrease due to air mixing into the pump) for a predetermined time (when water is dropped due to air mixing). If the operation continues for a predetermined allowable operating time within a range not exceeding the expected time), the pump driven by the electric motor is stopped, and the other pumps that are stopped are operated.
以下に本発明の一実施例を第１図より第４図により説
明する。第１図、第２図は本発明を実施するための給水
装置の一実施例を示す構成図である。第１図において、
PWは電源、MBは配線用遮断器、CT−１、CT−２は主回路
を流れる電流を検出して適正な電流値に変流する変流
器、MC1a、MC2aは電磁接触器、MC−１、MC−２の接点、
4a−１、4a−２は電動器を過負荷運転より保護するサー
マルリレー、３−１、３−２は電動機である。R1Sは配
線用遮断器MBの２次側より取った制御電源、SSは運転、
停止切替用のスイッチ、Ｔは例えばAC200V交流を低電圧
の直流（5V、12V）に変換して供給する安定上電源ユニ
ット、MC1、MC2は電磁接触器である。MCONはマイクロコ
ンピュータ（以下にマイコンと略称する）、CPUは中央
演算処理装置、ＭはRAMやROMからなるメモリ、Ｚは電源
接続端子、PIO−１〜PIO−３は各種入出力ポートであ
る。またDS1はポンプ電動機の運転下限電流ISを予め設
定する８ビットのディップスイッチ、DS2はポンプ電動
機の運転上限電流ILを予め設定するディップスイッチで
ある。I/O−１は変流器CTの検出した電動機３の運転電
流ＩをマイコンMCONの入出力ポートPIO−１を介して読
み込むとともに、ディップスイッチDS1、DS2により予め
設定してあるポンプ３の運転下限電流IS、運転上限電流
ILなどのデータを同じく入出力ポートPIO−１を介して
読み込むためのインタフェースである。PSは圧力スイッ
チ８または流量スイッチ10（第２図）の接点、I/O−２
は接点PSの信号を入出力ポートPIO−２より読み込むイ
ンタフェース、I/O−３は入出力ポートPIO−３から電磁
接触器MCをON−OFF制御するためのインタフェースであ
る。第２図において、１は受水槽、２−１、２−２は吸
水管、３−１、３−２は電動機、４−１、４−２はポン
プ、５−１、５−２は仕切弁、６−１、６−２は逆止め
弁、７は内部に空気溜まりを有する圧力タンク、８は圧
力スイッチ、９は給水管、10は流量スイッチ、11は、第
１図で示した制御回路である。第３図は、本実施例の給
水装置のポンプ運転特性図であり、縦軸に圧力Ｈ、横軸
に水量Ｑを取って示す。同図において曲線Ａはポンプの
Ｑ−Ｈ特性、曲線Ｂは電動機の負荷カーブ即ち電流曲
線、P1はポンプの始動圧力でQ1はその時の揚水量を表し
ている。前途した圧力スイッチ８はP1で閉じ、復帰圧力
Ｐ′１で開くように設定してある。またIOFFはポンプの
停止指令電流、ISはディップスイッチで設定される運転
下限電流、同じくILは運転上限電流である。第４図は本
発明実施例第１図に示した制御装置の動作手順を示した
フローチャートであり、この図面により給水装置の作動
を詳細に説明する。本実施例はポンプを２台使用し、交
互運転を行う給水装置で運転下限電流ISの許容運転時間
tSを30秒、運転上限電流ILの許容運転時間tLを60秒に設
定し、異常電流の許容繰り返し回数を３回としたものを
一例として上げている。第１図において、配線用遮断器
MBを投入し、スイッチSSを閉じるとマイコンMCONの電源
端子Ｚに安定化電源ユニットＴを介して、電力が供給さ
れる。この時、マイコンMCONは第４図の401ステップの
初期設定が実行される。次に402ステップにおいてディ
ップスイッチDS−１、DS−２にて設定されている、運転
下限電流IS、電源上限電流ILをインタフェースI/O−
１、入出力ポートPIO−１を介して読み込み、このデー
タをメモリＭに格納する。そして圧力スイッチ８の接点
PSの信号をインタフェースI/O−２、入出力ポートPIO−
２を介して読み込み、ON、OFF判定を実行し、結果をメ
モリＭに格納する。次に403ステップで給水圧力が始動
圧力以下に達しているか判定する。判定した結果、始動
圧力P1以下であれば、次の405ステップへ進み、入出力
ポートPIO−３よりインタフェースI/O−３を介して、電
磁開閉器MC1を励磁させ、電動機３−１を駆動し、ポン
プ４−１の運転を開始する。次に405ステップで電動機
の運転電流Ｉを測定して次の406ステップで運転下限電
流ISと比較する。空気の混入等によりＩがIS以下であれ
ば第５図の501−Ａステップにおいて、運転電流Ｉが運
転下限電流IS以下となっている時間ｔの計測を開始す
る。次に502−Ａステップにおいて、ｔが許容時間tSを
上回っているか判断する。ｔが30秒以下の場合は503−
Ａ、504−Ａステップで再び電流検出を行い、運転電流
ＩがISを上回った場合、回復と見なし、第４図の407ス
テップへ進む。ｔがtLを上回った場合は電流異常と見な
し、505−Ａステップで、異常回数NSのカウントを行
う。NSの初期値は０であり、ポンプ４−１の次回運転時
に同様の電流異常が見られなければ、再び０にリセット
される。次に506−Ａステップで異常回数NSの判定を行
い、NSが３回目の場合、ポンプ４は異常と見なし、507
−Ａステップでポンプ４−１の運転を中止し、508−Ａ
で警告ランプで故障を知らせた後、402−２ステップへ
行き、ポンプ４−２の運転へと切換える。また406ステ
ップでＩ≧ISの場合（正常状態）、407ステップへ進み
運転電流Ｉと運転上限電流ILの比較を行う。ＩがIL以上
の値を示した場合、第５図の501−Ｂステップへ進み、
以下前述の501−Ａ〜508−Ａステップと同様の動作を行
う。407ステップでＩ≦IL（正常状態）の場合は408ステ
ップへ進み、運転電流Ｉとポンプ停止指令電流IOFFの比
較を行う。比較した結果、Ｉ＞IOFFであれば402ステッ
プへ戻り動作を繰り返す。Ｉ＜IOFFであれば409ステッ
プにおいてポンプ４−１を停止させる。そして402−２
ステップへ進み、同様にしてポンプ４−２の運転を行
う。以下前述した手順に従って制御動作を繰返し、需要
水量に応じて給水を行ってゆくものである。前述の実施
例ではポンプの上限、下限電流をディップスイッチによ
り設定できるようにしたが、必要に応じてこれらの値を
メモリＭにデータとして予め書き込んでおいても良い。An embodiment of the present invention will be described below with reference to FIGS. 1 and 2 are configuration diagrams showing one embodiment of a water supply device for carrying out the present invention. In FIG.
PW is a power supply, MB is a circuit breaker, CT-1 and CT-2 are current transformers that detect the current flowing in the main circuit and transform to an appropriate current value, MC1a and MC2a are electromagnetic contactors, MC- 1, MC-2 contacts,
4a-1 and 4a-2 are thermal relays for protecting the motor from overload operation, and 3-1 and 3-2 are motors. R 1 S is the control power from the secondary side of the circuit breaker MB, SS is the operation,
A switch T for stop switching is a stable power supply unit that converts, for example, AC200V AC to low-voltage DC (5V, 12V) and supplies it. MC1 and MC2 are electromagnetic contactors. MCON is a microcomputer (hereinafter abbreviated as a microcomputer), CPU is a central processing unit, M is a memory composed of RAM and ROM, Z is a power supply connection terminal, and PIO-1 to PIO-3 are various input / output ports. The DS1 is 8-bit DIP switch for setting the operation limit current I S of the pump motor in advance, DS2 is DIP switch for setting the operation limit current I L of the pump motor in advance. The I / O-1 reads the operating current I of the electric motor 3 detected by the current transformer CT via the input / output port PIO-1 of the microcomputer MCON, and operates the pump 3 preset by the dip switches DS1 and DS2. Lower limit current I S , operation upper limit current
An interface for reading data, such as I L also via the output port PIO-1. PS is the contact of pressure switch 8 or flow switch 10 (Fig. 2), I / O-2
Is an interface for reading the signal of the contact PS from the input / output port PIO-2, and I / O-3 is an interface for ON / OFF-controlling the electromagnetic contactor MC from the input / output port PIO-3. In FIG. 2, 1 is a water receiving tank, 2-1 and 2-2 are suction pipes, 3-1 and 3-2 are electric motors, 4-1 and 4-2 are pumps, and 5-1 and 5-2 are partitions. Valves, 6-1 and 6-2 are check valves, 7 is a pressure tank having an air reservoir inside, 8 is a pressure switch, 9 is a water supply pipe, 10 is a flow switch, and 11 is the control shown in FIG. Circuit. FIG. 3 is a pump operation characteristic diagram of the water supply device of the present embodiment, in which the vertical axis represents the pressure H and the horizontal axis represents the water amount Q. Curve A in the drawing Q-H characteristics of the pump, the curve B the load curve or current curve of the motor, P 1 is Q 1 is represents a pumping amount at that time in the start-up pressure of the pump. Pressure switch 8 which is ahead is is set to close at P 1, open in the return pressure P '1. The I OFF pump stop command current, I S operating limit current set by DIP switch, is also I L is an operating limit current. FIG. 4 is a flowchart showing an operation procedure of the control device shown in FIG. 1 of the embodiment of the present invention, and the operation of the water supply device will be described in detail with reference to this drawing. This embodiment uses two pumps, allowable operating time of the operating limit current I S in water supply apparatus which performs the alternate operation
The t S 30 seconds, to set the allowable operation time t L of the operation limit current I L in 60 seconds, and raising those three times the allowable number of repetitions of abnormal current as an example. In FIG. 1, a circuit breaker for wiring
When the MB is turned on and the switch SS is closed, power is supplied to the power supply terminal Z of the microcomputer MCON via the stabilized power supply unit T. At this time, the microcomputer MCON performs the initial setting of step 401 in FIG. Next is set by DIP switch DS-1, DS-2 in 402 steps, the operating limit current I S, the power upper limit current I L interface I / O-
1. Read via the input / output port PIO-1, and store this data in the memory M. And the contact of pressure switch 8
PS signal is sent to interface I / O-2, input / output port PIO-
2, execute ON / OFF determination, and store the result in the memory M. Next, in step 403, it is determined whether the feed water pressure has reached the starting pressure or less. As a result of the determination, if the starting pressure P 1 or less, the process proceeds to the next 405 steps, via the interface I / O-3 from output port PIO-3, to excite the electromagnetic switch MC1, the motor 3-1 It drives and starts the operation of the pump 4-1. Then 405 measures the operating current I of the motor in step compared to the operating limit current I S in the next 406 steps. If I is equal to or smaller than I S due to air mixing or the like, measurement of the time t during which the operating current I is equal to or smaller than the operation lower limit current I S is started in step 501-A of FIG. Next, at 502-A step, t is judged whether or exceeds the permissible time t S. If t is less than 30 seconds, 503-
Performed again current detected by the A, 504-A step, when the operating current I exceeds the I S, regarded as recovered, the process proceeds to 407 steps of Figure 4. If t exceeds the t L regarded as current abnormality, at 505-A step, to count the number of malfunctions N S. The initial value of N S is 0, if the same current abnormality was observed at the next operation of the pump 4-1 it is reset to 0 again. Then a determination is abnormal number N S at 506-A step, if N S is the third, the pump 4 is regarded as abnormal, 507
In the -A step, the operation of the pump 4-1 is stopped, and the 508-A
After notifying the failure by a warning lamp, the process goes to the step 402-2 and switches to the operation of the pump 4-2. In the case of I ≧ I S at 406 steps (normal state), it is compared with the advances operating current I to 407 step operation upper limit current I L. If I showed a value of more than I L, the process proceeds to 501-B Step of FIG. 5,
Hereinafter, the same operation as the above-described steps 501-A to 508-A is performed. If I ≦ IL (normal state) in step 407, the process proceeds to step 408, where the operation current I and the pump stop command current I OFF are compared. As a result of comparison, if I> I OFF , the process returns to step 402 and repeats the operation. If I <I OFF , the pump 4-1 is stopped at step 409. And 402-2
Proceeding to the step, the pump 4-2 is similarly operated. Hereinafter, the control operation is repeated according to the above-described procedure, and water is supplied according to the demand water amount. In the above-described embodiment, the upper and lower limit currents of the pump can be set by the dip switches. However, these values may be written in the memory M as data as needed.
以上説明のように、本発明によれば、給液への空気混
入による運転電流の低下が予め決めた一定時間以上続く
ことにより、落水を予知して当該ポンプを停止し、休止
中のポンプを運転するようにしたので、落水を未然に防
止することができる効果を奏する。As described above, according to the present invention, the decrease in the operating current due to the incorporation of air into the liquid supply continues for a predetermined period of time or more. Since the vehicle is driven, it is possible to prevent the water from falling.
第１図は本発明の一実施例における給水装置の制御回路
図、第２図は本実施例の給水装置の系統図、第３図は本
実施例のポンプの運転特性図、第４図および第５図は第
２図の制御回路の制御手順を示すフローチャートであ
る。 ３−１、３−２……電動機、４−１、４−２……ポン
プ、７……圧力タンク、８……圧力スイッチ、９……給
水管、10……流量スイッチ、CT……変流器（電流検出手
段）、MC1、MC2……電磁開閉器、MCON……マイコン、I/
O−１、I/O−２……入出力ポートFIG. 1 is a control circuit diagram of a water supply device according to an embodiment of the present invention, FIG. 2 is a system diagram of the water supply device of the embodiment, FIG. 3 is an operation characteristic diagram of a pump of the embodiment, FIG. FIG. 5 is a flowchart showing a control procedure of the control circuit of FIG. 3-1, 3-2 ... electric motor, 4-1 4-2 ... pump, 7 ... pressure tank, 8 ... pressure switch, 9 ... water supply pipe, 10 ... flow switch, CT ... change Current source (current detection means), MC1, MC2 …… Electromagnetic switch, MCON …… Microcomputer, I /
O-1, I / O-2 ... I / O ports
フロントページの続き (58)調査した分野(Int.Cl.6，ＤＢ名) F04B 23/00 F04B 49/00Continuation of front page (58) Field surveyed (Int.Cl. 6 , DB name) F04B 23/00 F04B 49/00
Claims (1)
機と、ポンプ吐出側にある圧力タンクと、給水管と、こ
れに備わる圧力センサーを有し、前記圧力センサーの信
号を基に、給水量の変動に応じて、前記ポンプをある定
められた順序に従って運転する給水装置において、 前記電動機の電流を検出する電流検出手段と、ポンプ内
への空気混入による負荷低下を予測して予め決めた電動
機の運転下限電流値を設定する手段と、空気混入による
落水が起こると予想される時間を超えない範囲で予め決
めた許容運転時間を設定する手段と、前記電流検出手段
により検出された電流値が運転下限電流値以下になった
ことを検知する手段と、該検知されている時間が連続し
て前記許容運転時間以上続いたことを判定する手段と、
該手段により前記許容運転時間以上続いたと判定された
ら当該電動機で駆動されているポンプを停止させ休止中
の他のポンプを運転させる手段を備えたことを特徴とす
る給水装置。1. An apparatus comprising two or more pumps, an electric motor for driving the pumps, a pressure tank on a pump discharge side, a water supply pipe, and a pressure sensor provided on the pump, based on a signal from the pressure sensor. In a water supply device that operates the pump in accordance with a predetermined order according to a change in water supply amount, a current detection unit that detects a current of the electric motor, and a load reduction due to air mixing into the pump is predicted and determined in advance. Means for setting an operation lower limit current value of the motor, means for setting a predetermined allowable operation time within a time period not expected to cause water drop due to air mixing, and a current detected by the current detection means. Means for detecting that the value has become equal to or less than the operation lower limit current value, and means for determining that the time during which the value has been detected has continuously continued for the allowable operation time or more,
A water supply device, comprising: means for stopping a pump driven by the electric motor when the means determines that the operation has continued for the allowable operation time or longer, and for operating another pump that is inactive.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2242324A JP2766060B2 (en) | 1990-09-14 | 1990-09-14 | Water supply device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2242324A JP2766060B2 (en) | 1990-09-14 | 1990-09-14 | Water supply device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH04124474A JPH04124474A (en) | 1992-04-24 |
| JP2766060B2 true JP2766060B2 (en) | 1998-06-18 |
Family
ID=17087514
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2242324A Expired - Fee Related JP2766060B2 (en) | 1990-09-14 | 1990-09-14 | Water supply device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2766060B2 (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5047747B2 (en) * | 2007-10-01 | 2012-10-10 | 株式会社荏原製作所 | Operation control device and operation control method for horizontal axis pump |
| JP5317579B2 (en) * | 2008-08-20 | 2013-10-16 | 三洋電機株式会社 | Air conditioner |
| JP5862513B2 (en) * | 2012-08-23 | 2016-02-16 | 国産電機株式会社 | Control method and control device for oil pump for two-cycle engine |
| JP2020007909A (en) * | 2016-11-01 | 2020-01-16 | 日本電産テクノモータ株式会社 | Pump device and control method of pump device |
| CN107504551A (en) * | 2017-08-30 | 2017-12-22 | 宗永红 | A kind of separated electric heating installation |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6045759B2 (en) * | 1979-01-24 | 1985-10-11 | 株式会社日立製作所 | How to operate a water supply device with a pressure tank |
| JPS6073075A (en) * | 1983-09-28 | 1985-04-25 | Kawamoto Seisakusho:Kk | Method of detecting failure of pump device |
| JPS6189988A (en) * | 1984-10-09 | 1986-05-08 | Nippon Sogo Meintenansu:Kk | Protective control circuit for storage pump |
-
1990
- 1990-09-14 JP JP2242324A patent/JP2766060B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH04124474A (en) | 1992-04-24 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |