JP3702364B2

JP3702364B2 - Horizontal shaft pump

Info

Publication number: JP3702364B2
Application number: JP2001002409A
Authority: JP
Inventors: 英樹鹿毛; 哲郎南嶋; 健之大村; 正二大塚; 道明根岸; 俊明山本
Original assignee: 株式会社電業社機械製作所; 国土交通省九州地方整備局長; 社団法人河川ポンプ施設技術協会
Priority date: 2001-01-10
Filing date: 2001-01-10
Publication date: 2005-10-05
Anticipated expiration: 2021-01-10
Also published as: JP2002206494A

Description

【０００１】
【発明の属する技術分野】
本発明は、満水装置を有する横軸ポンプに関するものである。また、この満水装置で先行待機運転を継続する横軸ポンプに関するものである。
【０００２】
【従来の技術】
従来の満水装置を有する横軸ポンプの一例を図８を参照して簡単に説明する。図８は、従来の満水装置を有する横軸ポンプの一例の全体構造図である。
【０００３】
図８において、横軸ポンプは、ポンプケーシング１０の上流側に吸込エルボ１２を介して吸込管１４が連接されこの吸込管１４の先端部の吸込口１６が吸込水槽１８の水面下に没入され、またポンプケーシング１０の下流側にルーズ短管２０を介して吐出弁２２が設けられ、さらに吐出弁２２に吐出管２４が連接され、この吐出管２４の先端部の吐出口２６が吐出水槽２８の水面下に没入される。そして、吸込エルボ１２の壁を水平方向に主軸３０が貫通し、この主軸３０の一端に羽根車３２が固定されて、ポンプケーシング１０内で回転自在に配設される。主軸３０の他端は、減速機３４を介して電動機３６に駆動連結される。
【０００４】
また、ポンプケーシング１０の上部に開口部３８が穿設され、この開口部３８が満水検出手段４０に連通され、この満水検出手段４０に吸気管４２の一端が連通される。この吸気管４２は２つに分岐され、一方の分岐は真空遮断弁４４を介して真空ポンプ４６に連通され、他方の分岐は真空破壊弁４８を介して大気に開放される。そして、満水検出手段４０で満水を検出すると、その信号が制御手段５０に与えられ、真空遮断弁４４を閉塞させるとともに真空ポンプ４６の運転が停止される。なお、満水操作では、真空破壊弁４８は閉塞され真空遮断弁４４は開成されて真空ポンプ４６が運転されることは勿論である。そして、横軸ポンプの運転が停止されると、真空破壊弁４８が開成されてポンプケーシング１０内から落水がなされる。
【０００５】
【発明が解決しようとする課題】
上述の従来の横軸ポンプにあっては、満水検知手段４０で満水が検出されて、制御手段５０は直ちに、真空遮断弁４４を閉塞するとともに真空ポンプ４６の運転を停止する。しかし、真空遮断弁４４が完全に閉塞されるまでの間に、ポンプケーシング１０内の水が吸気管４２を介して真空ポンプ４６に流入する虞がある。そこで、真空ポンプ４６は、水が流入しても良い液封式が用いられていた。この液封式の真空ポンプ４６のために、図示しない貯水ポンプや給水ポンプが必要となる。また、流水が汚濁していたり海水が混入する場合には、これらが真空ポンプ４６に流入することで、真空ポンプの羽根車やケーシングなどを摩耗させまたは腐食させて、その寿命を低下させるという不具合が生じていた。
【０００６】
本発明は、上述のごとき従来技術の不具合を改善すべくなされたもので、真空ポンプに水が流入しないようにし、また先行待機運転を容易に継続できるようにした横軸ポンプを提供することを目的とする。
【０００７】
【課題を解決するための手段】
かかる、目的を達成するために、本発明の横軸ポンプは、吸込水槽に垂下される吸込管が連接される吸込エルボまたはこの吸込エルボに連接されるポンプケーシングまたはこのポンプケーシングに連接されるルーズ短管の上部に開口部を設け、この開口部に一端が連通する吸気管に立ち上がり部を形成し、この吸気管に真空遮断弁を介装し、前記吸気管の他端側を２つに分岐し、一方の分岐を真空ポンプに連通し、他方の分岐を圧力調整弁に連通し、この圧力調整弁の調整により前記真空ポンプにより得られる前記吸気管内の最低絶対圧力Ｐ２（ｋＰａ）と、前記開口部から前記立ち上がり部の頂点までの高さｈ１（ｍ）と、満水操作が行われる前記吸込水槽の最高水位から前記開口部までの高さｈ２（ｍ）と、満水操作が行われる前記吸込水槽の最低水位から前期最高水位までの高さｈ３（ｍ）とを、
ｈ１＋ｈ２＞１０−（Ｐ２／９．８）＞ｈ２＋ｈ３
となるように構成されている。
【０００８】
そして、前記開口部に満水検知手段を設け、この満水検知手段で満水が検出された後も前記真空遮断弁の開成を継続するとともに前記真空ポンプの運転を継続して先行待機運転とし、羽根車を始動する直前に前記真空遮断弁を閉塞してポンプ運転を行うように構成することもできる。
【０００９】
また、前記開口部に満水検知手段を設け、この満水検知手段が満水を検知した所定時間後に前記真空遮断弁を閉塞するとともに前記真空ポンプの運転を停止し、前記吸気管内の水位が低下して前記満水検知手段で満水が検出されなくなると、前記真空遮断弁を開成するとともに前記真空ポンプの運転を再開して先行待機運転を継続するように構成することもできる。
【００１０】
さらに、前記開口部に満水検知手段を設け、前記吸気管の前記立ち上がり部に上限水位検知手段と下限水位検知手段とを設け、前記満水検知手段が満水を検出し、さらに前記上限水位検知手段で前記吸気管内の水位が上限水位となったことを検出すると、前記真空遮断弁を閉塞するとともに前記真空ポンプの運転を停止し、前記下限水位検知手段で前記吸気管内の水位が下限水位以下となったことを検出すると、前記真空遮断弁を開成するとともに前記真空ポンプの運転を再開して先行待機運転を継続するように構成することもできる。
【００１１】
そしてまた、前記吸気管の前記立ち上がり部の少なくとも一部を貯水容量の大きな太径として構成することも可能である。
【００１２】
さらにまた、横軸ポンプを、前記吸込水槽の最高水位と最低水位を同じにして複数台配設し、これらの複数台の横軸ポンプのそれぞれの前記開口部に連通する吸気管を１本の配管に集合して前記真空ポンプに連通して構成することも可能である。
【００１３】
【発明の実施の形態】
以下、本発明の第１実施例を図１を参照して説明する。図１は、本発明の横軸ポンプの第１実施例の全体構成図である。図１において、図８と同じまたは均等な部材には同じ符号を付けて重複する説明を省略する。
【００１４】
図１において、ポンプケーシング１０の上部に穿設された開口部３８が満水検知手段４０を介して、立ち上がり部４２ａが形成された吸気管４２の一端に連通され、この吸気管４２に真空遮断弁４４が介装され、吸気管４２の他端が真空ポンプ５２に連通される。そして、満水検知手段４０で満水を検知した信号が制御手段５４に与えられ、この制御手段５４の信号で真空遮断弁４４が制御される。
【００１５】
そして、真空ポンプ５２の最低絶対圧力Ｐ１（ｋＰａ）と、開口部３８から吸気管４２の立ち上がり部４８ａの頂点までの高さｈ１（ｍ）と、満水操作がなされる吸込水槽１８の最高水位ＷＨから開口部３８までの高さｈ２（ｍ）と、満水操作がなされる最低水位ＷＬと最低水位ＷＨまでの高さｈ３（ｍ）とが、
ｈ１＋ｈ２＞１０−（Ｐ１／９．８）＞ｈ２＋ｈ３
の関係に設定される。
【００１６】
これは、吸込水槽１８の最低水位ＷＬの状態で満水操作を行った際に、吸込水槽１８の水を開口部３８まで吸い上げるためには、真空ポンプ５２の最低絶対圧力Ｐ１（ｋＰａ）は、ｈ２＋ｈ３の水柱を保持できる真空能力が必要である。そこで
１０−（Ｐ１／９．８）＞ｈ２＋ｈ３
である必要がある。
【００１７】
そして、真空ポンプ５２の真空能力が大きすぎると、吸込水槽１８の水が開口部３８と吸気管４２の立ち上がり部４８ａの頂点を超えて真空ポンプ５２に流入する。これを防ぐためには、吸込水槽の最高水位ＷＨの状態で満水操作を行った際に、真空ポンプ５２がｈ１＋ｈ２の水柱を保持できない真空能力であれば良い。そこで、
ｈ１＋ｈ２＞１０−（Ｐ１／９．８）
である必要がある。
【００１８】
なお、上記２つの関係式から、ｈ１＞ｈ３でなければならないことは当然である。そして、真空ポンプ５２の最低絶対圧力Ｐ１に応じて、吸気管４２の立ち上がり部４８ａの高さｈ１を適宜に設定すれば良い。また、吸気管４２の立ち上がり部４２ａの高さｈ１に応じて、適宜な最低絶対圧力Ｐ１を有する真空ポンプ５２を選定しても良い。
【００１９】
かかる構成において、吸込水槽１８の水位が最高水位ＷＨと最低水位ＷＬの間にある状態で満水操作がなされるが、真空遮断弁４４を開成するとともに真空破壊弁４８を閉塞して真空ポンプ５２が運転される。すると、吸込水槽１８の水が吸い上げられ満水検知手段４０で満水が検知され、さらに吸気管４２の立ち上がり部４２ａの途中まで水位が上昇する。制御手段５４は、満水検知手段４０で満水が検知されても、真空遮断弁４４を閉塞することなく開成を維持し、また真空ポンプ５２の運転を継続する。この吸気管４２の立ち上がり部４２ａの途中までの水位は、それ以上に上昇して立ち上がり部４２ａの頂点を超えることがない。したがって、真空ポンプ５２には水が流入することがない。そこで、真空ポンプ５２に、乾式の真空ポンプを使用することができる。また、吸気管４２の立ち上がり部４２ａの途中に水位がある状態が継続され、先行待機運転が簡単に継続され得る。そして、横軸ポンプを運転する直前に、制御手段５４は、満水検知手段４０で満水が検知されていることを条件として、真空遮断弁４４を閉塞するとともに真空ポンプ５２を停止する。そして、電動機３６の駆動により羽根車３２が回転されてポンプ運転がなされる。
【００２０】
次に、本発明の第２実施例を図２ないし図４を参照して説明する。図２は、本発明の横軸ポンプの第２実施例の全体構造図である。図３は、図２の圧力調整弁の一例の縦断面図である。図４は、図３の圧力調整弁で調整される吸気管内の最低絶対圧力を示す特性図である。図２において、図１と同じまたは均等な部材には同じ符号を付けて重複する説明を省略する。
【００２１】
図２に示す第２実施例で、図１に示す第１実施例と相違するとことは、吸気管４２の他端側が２つに分岐され、一方の分岐が真空ポンプ５２に連通され、他方の分岐が圧力調整弁５６に連通されたことにある。この圧力調整弁５６は、図３に示すごとく、一例として箱体６０に穿設されて大気に連通する開口６２を、弁体６４が閉塞するように当接し、この弁体６４がバネ６６の弾力で付勢され、このバネ６６の弾力が調整ネジ６８で調整される。かかる圧力調整弁５６にて、調整ネジ６８を適宜に設定することで、図４に示すごとく、吸気管４２内の最低絶対圧力Ｐ２（ｋＰａ）が所望の大きさで、弁体６４を開口させることができる。
【００２２】
そして、圧力調整弁５６で調整された吸気管４２内の最低絶対圧力Ｐ２（ｋＰａ）が、第１実施例と同様に、
ｈ１＋ｈ２＞１０−（Ｐ２／９．８）＞ｈ２＋ｈ３
となるようにすることで、吸込水槽１８の水位が最高水位ＷＨと最低水位ＷＬの間であれば、開口部３８まで水を吸い上げて満水操作が可能であり、しかも吸気管４２の立ち上がり部４２ａの頂点までは水位が達することがなく、真空ポンプ１２に水が流入するようなことがない。なお、真空ポンプ５２自体の最大能力としての最低絶対圧力は、圧力調整弁５６で調整される最低絶対圧力Ｐ２よりも低いことは勿論である。
【００２３】
かかる構成の第２実施例では、吸気管４２の立ち上がり部４２ａの高さに応じて、吸気管４２内の最低絶対圧力Ｐ２を簡単に調整ができる。そこで、真空ポンプ５２の選定が制限を受けるようなことがない。しかも、第１実施例と同様に、満水操作ができるとともに、先行待機運転を簡単に維持させることができる。
【００２４】
さらに、本発明の第３実施例を図５を参照して説明する。図５は、本発明の第３実施例の複数台の横軸ポンプの全体構成図である。図５において、図１と同じまたは均等な部材には同じ符号を付けて重複する説明を省略する。
【００２５】
図５に示す第３実施例では、横軸ポンプが複数台配設され、、吸込水槽１８の同じ最高水位ＷＨと最低水位ＷＬの間で満水操作がなされる。そして、それぞれの開口部３８，３８，３８が、満水検知手段４０，４０，４０と真空遮断弁４４，４４，４４をそれぞれに介して吸気管４２に連通し、これらが１本の配管に集合されて立ち上がり部４２ａを経て１台の真空ポンプ５２に連通される。この真空ポンプ５２の最低絶対圧力Ｐ１は、第１実施例と同様に設定される。
【００２６】
かかる構成の第３実施例において、満水操作で真空遮断弁４４，４４，４４を開成して真空ポンプ５２を運転する。すると、吸気管４２の立ち上がり部４２ａの途中まで水位が上昇し、いずれの横軸ポンプも満水となる。そこで、吸込水槽１８への流入量に応じて必要な台数の横軸ポンプを始動させるが、制御手段５４は、運転する横軸ポンプの真空遮断弁４４を、始動直前に閉塞する。他の運転されない横軸ポンプでは、先行待機運転が継続される。
【００２７】
そしてさらに、本発明の第４実施例を図６を参照して説明する。図６は、本発明の第４実施例の複数台の横軸ポンプの全体構成図である。図６において、図１と同じまたは均等な部材には同じ符号を付けて重複する説明を省略する。
【００２８】
図６に示す第４実施例では、横軸ポンプが複数台配設され、吸込水槽１８の同じ最高水位ＷＨと最低水位ＷＬの間で満水操作がなされる。そして、それぞれの開口部３８，３８，３８が満水検知手段４０，４０，４０と遮断弁７０，７０，７０をそれぞれに介して吸気管４２に連通し、これらが１本の配管に集合されて立ち上がり部４２ａを経て、１台の真空遮断弁４４を介して１台の真空ポンプ５２に連通される。この真空ポンプ５２の最低絶対圧力Ｐ１は、第１実施例と同様に設定される。
【００２９】
かかる構成の第４実施例において、満水操作で真空遮断弁４４と遮断弁７０，７０，７０をいずれも開成して真空ポンプ５２を運転する。すると、満水検知手段４０，４０，４０の全てで満水が検知されると図示しないタイマーが起動され、所定時間後に真空遮断弁４４が閉塞されるとともに真空ポンプ５２が停止される。ここで、吸気管４２の立ち上がり部４２ａの途中まで水位は上昇している。そこで、複数台の横軸ポンプがいずれも先行待機運転となる。そして、運転する横軸ポンプの遮断弁７０を制御手段５４で閉塞して、ポンプの運転を始動させる。他の横軸ポンプは先行待機運転が継続される。かかる先行待機運転で、吸気管４２内の負圧が低下して水位が低下し、いずれかの満水検知手段４０で満水が検知されなくなれば、再び真空遮断弁４４を開成するとともにタイマーにより所定時間だけ真空ポンプ５２を運転すれば良い。このように、真空遮断弁４４の閉塞と開成および真空ポンプ５２の運転と停止を適宜に繰り返して行うことで、先行待機運転を継続させることができる。しかも、真空ポンプ５２を必要に応じて運転するので、常に運転するものに比較して、消費動力が低減される。
【００３０】
図７は、第４実施例における真空ポンプの運転停止制御の別の構造を示し、吸気管の立ち上がり部に設けられた太径部の縦断面図である。図７で、太径部７２には、上限水位検知手段７４とこれより低い位置に下限水位検知手段７６が設けられる。そして、満水操作で吸気管４２に水が吸い上げられ、立ち上がり部４２ａの太径部７２の上限水位検知手段７４で水位の上昇が検出されると、真空遮断弁４４を閉塞するとともに真空ポンプ５２を停止して先行待機運転とする。そして、立ち上がり部４２ａの水位が低下し、下限水位検知手段７６で水位が下限水位以下となったことを検出すると、真空遮断弁４４を開成するとともに真空ポンプ５２を再び運転する。かかる真空遮断弁４４と真空ポンプ５２の制御により、先行待機運転が継続される。そして、太径部７２は貯水容量を多くする目的で配設しており、貯水容量が多いほど水位の変動が少なくて真空ポンプ５２を運転する回数が少なく、真空ポンプ５２の起動に要する消費電力を削減することができる。
【００３１】
なお、上記実施例において、吸気管４２は、立ち上がり部４２ａの頂点を経て下り配管を介して真空ポンプ５２に連通され、真空ポンプ５２が電動機３６と同じ床に配設できるように構成されている。しかし、これに限られず、吸気管４２の立ち上がり部４２ａの頂点に真空ポンプ５２が連通していても良い。また、図７に示す構造では、上限水位検知手段７４を設けずに、下限水位検知手段７６のみを設け、満水検知手段４０または下限水位検知手段７６で水位の上昇が検出されてから所定時間経過後に真空遮断弁４４を閉塞するとともに真空ポンプ５２を停止し、下限水位検知手段７６で水位が下限水位以下となったのを検出すると、真空遮断弁４４を開成するとともに真空ポンプ５２を再び運転し、所定時間経過後に真空遮断弁４４を閉塞するとともに真空ポンプ５２を再び停止しても良い。さらに、図６に示す第４実施例で、真空遮断弁４４を省き、遮断弁７０，７０，７０をそれぞれ真空遮断弁として作用するように制御しても良い。そしてまた、図５に示す第３実施例で、吸気管４２の立ち上がり部４２ａに、図７のごとき貯水容量の多い太径部を設けても良い。またさらに、開口部３８は、ポンプケーシング１０の上部に設けられたものに限られず、上流側の吸込エルボ１２の上部または下流側のルーズ短管２０の上部に穿設されても良い。そして、開口部３８は１つに限られず複数設けられて、これらが連通されて満水検知手段４０に接続されても良い。そしてさらに、図５で示す第３実施例および図６で示す第４実施例において、吸気管４２が１本に集合された配管に連通する真空ポンプ５２は、上記実施例のものに限られず、真空能力を大きくするために複数台の真空ポンプが直列に連通されたものであっても良く、また不測の事態に備えて、２台の真空ポンプを並列に接続し、バルブの切換でいずれか一方の真空ポンプを配管に連通させるようにしても良い。他方は、予備の真空ポンプである。
【００３２】
【発明の効果】
以上説明したように、本発明の横軸ポンプを構成されているので、以下のごとき格別な効果を奏する。
【００３３】
請求項１記載の横軸ポンプにあっては、圧力調整弁の調整により吸気管内の最低絶対圧力Ｐ２を調整できる。そして、この最低絶対圧力Ｐ２と吸気管の立ち上がり部の頂点の高さを適宜に設定することで、満水操作で立ち上がり部の途中までしか水位が上昇せず、真空ポンプに水が流入しない。そこで、乾式の真空ポンプを使用でき、また流水が汚濁していたり海水が混入しても真空ポンプの寿命が低下するようなことがない。しかも、先行待機運転を簡単に継続させることができる。さらに、圧力調整弁で吸気管内の最低絶対圧力Ｐ２を簡単に調整することが可能である。
【００３４】
請求項２記載の横軸ポンプにあっては、先行待機運転で羽根車を始動する直前に真空遮断弁を閉塞することで、確実にポンプ運転が可能となる。
【００３５】
請求３および４記載の横軸ポンプにあっては、真空遮断弁と真空ポンプを適宜に制御して、先行待機運転を簡単に継続させることができる。しかも、真空ポンプの運転と停止の繰り返しにより、常に運転し続けるのに比べて、消費電力を低減できる。
【００３６】
請求項５記載の横軸ポンプにあっては、吸気管の立ち上がり部の一部を太径として貯水容量を多くしたので、先行待機運転で真空ポンプが停止されても吸気管内の水位の低下が緩やかであり、それだけ真空ポンプを運転する回数が少ない。もって、真空ポンプの起動に要する消費電力を低減できる。
【００３７】
請求項６記載の横軸ポンプにあっては、複数台の横軸ポンプを１台の真空ポンプで先行待機運転とすることができる。
【図面の簡単な説明】
【図１】本発明の横軸ポンプの第１実施例の全体構成図である。
【図２】本発明の横軸ポンプの第２実施例の全体構造図である。
【図３】図２の圧力調整弁の一例の縦断面図である。
【図４】図３の圧力調整弁で調整される吸気管内の最低絶対圧力を示す特性図である。
【図５】本発明の第３実施例の複数台の横軸ポンプの全体構成図である。
【図６】本発明の第４実施例の複数台の横軸ポンプの全体構成図である。
【図７】第４実施例における真空ポンプの運転停止制御の別の構造を示し、吸気管の立ち上がり部に設けられた太径部の縦断面図である。
【図８】従来の満水装置を有する横軸ポンプの一例の全体構造図である。
【符号の説明】
１０ポンプケーシング
１２吸込エルボ
１８吸込水槽
３２羽根車
３８開口部
４０満水検知手段
４２吸気管
４２ａ立ち上がり部
４４真空遮断弁
５２真空ポンプ
５４制御手段
５６圧力調整弁
７０遮断弁
７２太径部
７４上限水位検知手段
７６下限水位検知手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a horizontal shaft pump having a full water device. Further, the present invention relates to a horizontal axis pump that continues the preceding standby operation with the full water device.
[0002]
[Prior art]
An example of a horizontal axis pump having a conventional water filling device will be briefly described with reference to FIG. FIG. 8 is an overall structural diagram of an example of a horizontal axis pump having a conventional water filling device.
[0003]
In FIG. 8, in the horizontal axis pump, a suction pipe 14 is connected to the upstream side of the pump casing 10 via a suction elbow 12, and a suction port 16 at the tip of the suction pipe 14 is submerged below the surface of the suction water tank 18. Further, a discharge valve 22 is provided on the downstream side of the pump casing 10 through a loose short pipe 20, and a discharge pipe 24 is connected to the discharge valve 22, and a discharge port 26 at the tip of the discharge pipe 24 is connected to the discharge water tank 28. Immerse yourself under the water. The main shaft 30 penetrates the wall of the suction elbow 12 in the horizontal direction, and an impeller 32 is fixed to one end of the main shaft 30 so as to be rotatable in the pump casing 10. The other end of the main shaft 30 is drivingly connected to an electric motor 36 via a speed reducer 34.
[0004]
An opening 38 is formed in the upper part of the pump casing 10, and this opening 38 communicates with the full water detection means 40, and one end of the intake pipe 42 communicates with the full water detection means 40. This intake pipe 42 is branched into two, one branch is connected to a vacuum pump 46 via a vacuum shut-off valve 44, and the other branch is opened to the atmosphere via a vacuum breaker valve 48. When the full water detecting means 40 detects full water, the signal is given to the control means 50, the vacuum shut-off valve 44 is closed and the operation of the vacuum pump 46 is stopped. In the full water operation, the vacuum break valve 48 is closed and the vacuum shut-off valve 44 is opened, and the vacuum pump 46 is operated. When the operation of the horizontal axis pump is stopped, the vacuum breaker valve 48 is opened and water is dropped from the pump casing 10.
[0005]
[Problems to be solved by the invention]
In the above-described conventional horizontal axis pump, when the full water detection means 40 detects full water, the control means 50 immediately closes the vacuum shutoff valve 44 and stops the operation of the vacuum pump 46. However, the water in the pump casing 10 may flow into the vacuum pump 46 through the intake pipe 42 until the vacuum shut-off valve 44 is completely closed. Therefore, the vacuum pump 46 is a liquid ring type into which water may flow. For the liquid ring vacuum pump 46, a water storage pump or a water supply pump (not shown) is required. Also, when running water is polluted or seawater is mixed in, these flow into the vacuum pump 46, thereby causing the impeller or casing of the vacuum pump to wear or corrode, thereby reducing its life. Has occurred.
[0006]
The present invention has been made in order to improve the problems of the prior art as described above, and provides a horizontal shaft pump that prevents water from flowing into a vacuum pump and allows a prior standby operation to be easily continued. Objective.
[0007]
[Means for Solving the Problems]
In order to achieve the object, the horizontal axis pump of the present invention includes a suction elbow connected to a suction pipe suspended in a suction water tank, a pump casing connected to the suction elbow, or a loose connected to the pump casing. An opening is provided in the upper part of the short pipe, a rising part is formed in the intake pipe having one end communicating with the opening, a vacuum shutoff valve is interposed in the intake pipe, and the other end of the intake pipe is divided into two. Branching, one branch communicating with the vacuum pump, the other branch communicating with the pressure regulating valve, and a minimum absolute pressure P2 (kPa) in the intake pipe obtained by the vacuum pump by adjusting the pressure regulating valve; The height h1 (m) from the opening to the top of the rising part, the height h2 (m) from the highest water level of the suction water tank where the filling operation is performed to the opening, and the filling operation are performed. Suction From the lowest level of the tank up to the previous year high water height h3 and (m),
h1 + h2> 10− (P2 / 9.8)> h2 + h3
It is comprised so that.
[0008]
Then, a full water detecting means is provided at the opening, and after the full water detecting means is detected, the opening of the vacuum shut-off valve is continued and the operation of the vacuum pump is continued as a preliminary standby operation. It is also possible to perform the pump operation by closing the vacuum shut-off valve immediately before starting the operation.
[0009]
In addition, a full water detecting means is provided in the opening, and the vacuum shutoff valve is closed after a predetermined time when the full water detecting means detects full water, and the operation of the vacuum pump is stopped, and the water level in the intake pipe is lowered. When full water is no longer detected by the full water detecting means, the vacuum shut-off valve is opened and the operation of the vacuum pump is restarted to continue the preceding standby operation.
[0010]
Further, a full water detection means is provided at the opening, an upper limit water level detection means and a lower limit water level detection means are provided at the rising portion of the intake pipe, the full water detection means detects full water, and the upper limit water level detection means When it is detected that the water level in the intake pipe has reached the upper limit water level, the vacuum shut-off valve is closed and the operation of the vacuum pump is stopped, and the water level in the intake pipe becomes equal to or lower than the lower limit water level by the lower limit water level detection means. When this is detected, the vacuum shut-off valve can be opened and the operation of the vacuum pump can be resumed to continue the preceding standby operation.
[0011]
It is also possible to configure at least a part of the rising portion of the intake pipe as a large diameter having a large water storage capacity.
[0012]
Furthermore, a plurality of horizontal axis pumps are arranged with the highest water level and the lowest water level of the suction water tank being the same, and one intake pipe communicating with each of the openings of the plurality of horizontal axis pumps is provided. It is also possible to configure by collecting in a pipe and communicating with the vacuum pump.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, a first embodiment of the present invention will be described with reference to FIG. FIG. 1 is an overall configuration diagram of a first embodiment of a horizontal shaft pump according to the present invention. In FIG. 1, the same or equivalent members as in FIG.
[0014]
In FIG. 1, an opening 38 formed in the upper portion of the pump casing 10 communicates with one end of an intake pipe 42 formed with a rising portion 42a via a full water detection means 40, and a vacuum shut-off valve is connected to the intake pipe 42. 44 is interposed, and the other end of the intake pipe 42 is communicated with the vacuum pump 52. Then, a signal that the full water detection means 40 has detected full water is given to the control means 54, and the vacuum shut-off valve 44 is controlled by the signal from the control means 54.
[0015]
The minimum absolute pressure P1 (kPa) of the vacuum pump 52, the height h1 (m) from the opening 38 to the apex of the rising portion 48a of the intake pipe 42, and the maximum water level WH of the suction water tank 18 that is filled with water. Height h2 (m) from the opening 38 to the opening 38, and the minimum water level WL at which full operation is performed and the height h3 (m) to the minimum water level WH,
h1 + h2> 10− (P1 / 9.8)> h2 + h3
Is set to the relationship.
[0016]
This is because the minimum absolute pressure P1 (kPa) of the vacuum pump 52 is h2 + h3 in order to suck up the water in the suction water tank 18 to the opening 38 when the water filling operation is performed in the state of the minimum water level WL of the suction water tank 18. A vacuum capacity that can hold the water column is required. Therefore
10− (P1 / 9.8)> h2 + h3
Need to be.
[0017]
If the vacuum capacity of the vacuum pump 52 is too large, the water in the suction water tank 18 flows into the vacuum pump 52 beyond the apex of the opening portion 38 and the rising portion 48a of the intake pipe 42. In order to prevent this, it is sufficient if the vacuum capacity is such that the vacuum pump 52 cannot hold the h1 + h2 water column when the water filling operation is performed in the state of the maximum water level WH of the suction water tank. there,
h1 + h2> 10− (P1 / 9.8)
Need to be.
[0018]
Of course, from the above two relational expressions, h1> h3 must be satisfied. Then, the height h1 of the rising portion 48a of the intake pipe 42 may be set appropriately according to the minimum absolute pressure P1 of the vacuum pump 52. Further, the vacuum pump 52 having an appropriate minimum absolute pressure P1 may be selected according to the height h1 of the rising portion 42a of the intake pipe 42.
[0019]
In such a configuration, the water filling operation is performed in a state where the water level of the suction water tank 18 is between the highest water level WH and the lowest water level WL. However, the vacuum pump 52 is opened while the vacuum breaker valve 48 is closed and the vacuum pump 52 is closed. Driven. Then, the water in the suction water tank 18 is sucked up and full water is detected by the full water detection means 40, and the water level rises to the middle of the rising portion 42a of the intake pipe 42. Even when the full water detection means 40 detects full water, the control means 54 maintains the opening without closing the vacuum shutoff valve 44 and continues the operation of the vacuum pump 52. The water level up to the middle of the rising portion 42a of the intake pipe 42 does not rise further and exceed the apex of the rising portion 42a. Accordingly, water does not flow into the vacuum pump 52. Therefore, a dry vacuum pump can be used as the vacuum pump 52. Further, the state where the water level is in the middle of the rising portion 42a of the intake pipe 42 is continued, and the preceding standby operation can be easily continued. Then, immediately before the horizontal axis pump is operated, the control unit 54 closes the vacuum shut-off valve 44 and stops the vacuum pump 52 on condition that the full water detection unit 40 detects full water. And the impeller 32 is rotated by the drive of the electric motor 36, and a pump driving | operation is made.
[0020]
Next, a second embodiment of the present invention will be described with reference to FIGS. FIG. 2 is an overall structural view of a second embodiment of the horizontal axis pump of the present invention. FIG. 3 is a longitudinal sectional view of an example of the pressure regulating valve of FIG. FIG. 4 is a characteristic diagram showing the lowest absolute pressure in the intake pipe adjusted by the pressure regulating valve of FIG. In FIG. 2, the same or equivalent members as in FIG.
[0021]
The second embodiment shown in FIG. 2 differs from the first embodiment shown in FIG. 1 in that the other end side of the intake pipe 42 is branched into two, one branch communicates with the vacuum pump 52, and the other The branch is in communication with the pressure regulating valve 56. As shown in FIG. 3, the pressure regulating valve 56 contacts, for example, an opening 62 formed in the box body 60 and communicating with the atmosphere so that the valve body 64 closes the valve body 64. The spring 66 is urged by elasticity, and the elasticity of the spring 66 is adjusted by the adjusting screw 68. By appropriately setting the adjusting screw 68 in the pressure adjusting valve 56, as shown in FIG. 4, the minimum absolute pressure P2 (kPa) in the intake pipe 42 has a desired magnitude, and the valve body 64 is opened. be able to.
[0022]
The minimum absolute pressure P2 (kPa) in the intake pipe 42 adjusted by the pressure adjustment valve 56 is the same as in the first embodiment.
h1 + h2> 10− (P2 / 9.8)> h2 + h3
Thus, if the water level of the suction water tank 18 is between the highest water level WH and the lowest water level WL, water can be sucked up to the opening 38 and full operation can be performed, and the rising portion 42a of the intake pipe 42 can be obtained. The water level does not reach the top of the water, and water does not flow into the vacuum pump 12. Needless to say, the minimum absolute pressure as the maximum capacity of the vacuum pump 52 itself is lower than the minimum absolute pressure P2 adjusted by the pressure adjusting valve 56.
[0023]
In the second embodiment having such a configuration, the minimum absolute pressure P2 in the intake pipe 42 can be easily adjusted according to the height of the rising portion 42a of the intake pipe 42. Therefore, the selection of the vacuum pump 52 is not limited. In addition, as in the first embodiment, a full water operation can be performed and the preceding standby operation can be easily maintained.
[0024]
Furthermore, a third embodiment of the present invention will be described with reference to FIG. FIG. 5 is an overall configuration diagram of a plurality of horizontal shaft pumps according to the third embodiment of the present invention. In FIG. 5, the same or equivalent members as in FIG.
[0025]
In the third embodiment shown in FIG. 5, a plurality of horizontal axis pumps are provided, and a full water operation is performed between the same highest water level WH and lowest water level WL in the suction water tank 18. And each opening part 38,38,38 is connected to the intake pipe 42 via the full-water detection means 40,40,40 and the vacuum shut-off valves 44,44,44, respectively, and these are gathered in one piping. Then, it communicates with one vacuum pump 52 via the rising portion 42a. The minimum absolute pressure P1 of the vacuum pump 52 is set in the same manner as in the first embodiment.
[0026]
In the third embodiment having such a configuration, the vacuum pump 52 is operated by opening the vacuum shut-off valves 44, 44, 44 by a full water operation. Then, the water level rises to the middle of the rising portion 42a of the intake pipe 42, and all the horizontal axis pumps are full. Accordingly, the necessary number of horizontal axis pumps are started according to the amount of flow into the suction water tank 18, but the control means 54 closes the vacuum shut-off valve 44 of the horizontal axis pump to be operated immediately before the start. In other horizontal shaft pumps that are not operated, the preceding standby operation is continued.
[0027]
Further, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 6 is an overall configuration diagram of a plurality of horizontal shaft pumps according to the fourth embodiment of the present invention. In FIG. 6, the same or equivalent members as in FIG.
[0028]
In the fourth embodiment shown in FIG. 6, a plurality of horizontal axis pumps are arranged, and a full water operation is performed between the same highest water level WH and lowest water level WL in the suction water tank 18. And each opening part 38,38,38 is connected to the intake pipe 42 via the full water detection means 40,40,40 and the shutoff valve 70,70,70, respectively, and these are gathered in one piping. It communicates with one vacuum pump 52 via one vacuum shut-off valve 44 via the rising portion 42a. The minimum absolute pressure P1 of the vacuum pump 52 is set in the same manner as in the first embodiment.
[0029]
In the fourth embodiment having such a configuration, the vacuum pump 52 is operated by opening both the vacuum shut-off valve 44 and the shut-off valves 70, 70, 70 by a full water operation. Then, when full water is detected by all of the full water detecting means 40, 40, 40, a timer (not shown) is started, and after a predetermined time, the vacuum shut-off valve 44 is closed and the vacuum pump 52 is stopped. Here, the water level rises to the middle of the rising portion 42a of the intake pipe 42. Therefore, all of the plurality of horizontal axis pumps are in the standby standby operation. Then, the shutoff valve 70 of the operating horizontal axis pump is closed by the control means 54, and the operation of the pump is started. The other horizontal axis pumps continue the preceding standby operation. In such a preliminary standby operation, if the negative pressure in the intake pipe 42 decreases and the water level decreases and no full water is detected by any of the full water detection means 40, the vacuum shut-off valve 44 is opened again and a predetermined time is set by a timer. Only the vacuum pump 52 needs to be operated. In this manner, the preliminary standby operation can be continued by appropriately repeating the closing and opening of the vacuum shut-off valve 44 and the operation and stopping of the vacuum pump 52. In addition, since the vacuum pump 52 is operated as necessary, the power consumption is reduced as compared with the constant operation.
[0030]
FIG. 7 shows another structure of the vacuum pump operation stop control in the fourth embodiment, and is a longitudinal sectional view of a large diameter portion provided at the rising portion of the intake pipe. In FIG. 7, the large diameter portion 72 is provided with an upper limit water level detection means 74 and a lower limit water level detection means 76 at a lower position. Then, when water is sucked into the intake pipe 42 by the full operation and the rise of the water level is detected by the upper limit water level detection means 74 of the large diameter portion 72 of the rising portion 42a, the vacuum shutoff valve 44 is closed and the vacuum pump 52 is turned on. Stop and enter the standby operation. And if the water level of the rising part 42a falls and the lower limit water level detection means 76 detects that the water level has become below the lower limit water level, the vacuum shutoff valve 44 is opened and the vacuum pump 52 is operated again. By the control of the vacuum shut-off valve 44 and the vacuum pump 52, the advance standby operation is continued. The large-diameter portion 72 is arranged for the purpose of increasing the water storage capacity. The larger the water storage capacity, the less the fluctuation of the water level and the fewer the number of times the vacuum pump 52 is operated. Can be reduced.
[0031]
In the above embodiment, the intake pipe 42 communicates with the vacuum pump 52 via the descending pipe via the apex of the rising portion 42 a, and the vacuum pump 52 can be disposed on the same floor as the electric motor 36. . However, the present invention is not limited to this, and the vacuum pump 52 may communicate with the apex of the rising portion 42 a of the intake pipe 42. In the structure shown in FIG. 7, the upper limit water level detection means 74 is not provided, but only the lower limit water level detection means 76 is provided, and a predetermined time has elapsed since the rise of the water level was detected by the full water detection means 40 or the lower limit water level detection means 76. Later, the vacuum shutoff valve 44 is closed and the vacuum pump 52 is stopped. When the lower limit water level detecting means 76 detects that the water level is lower than the lower limit water level, the vacuum shutoff valve 44 is opened and the vacuum pump 52 is operated again. The vacuum shut-off valve 44 may be closed and the vacuum pump 52 may be stopped again after a predetermined time has elapsed. Further, in the fourth embodiment shown in FIG. 6, the vacuum shutoff valve 44 may be omitted, and the shutoff valves 70, 70, 70 may be controlled so as to act as vacuum shutoff valves, respectively. Further, in the third embodiment shown in FIG. 5, the rising portion 42a of the intake pipe 42 may be provided with a large diameter portion having a large water storage capacity as shown in FIG. Furthermore, the opening 38 is not limited to the one provided in the upper part of the pump casing 10, and may be formed in the upper part of the suction elbow 12 on the upstream side or the upper part of the loose short pipe 20 on the downstream side. And the opening part 38 is not restricted to one, A plurality may be provided, and these may communicate and be connected to the full water detection means 40. Furthermore, in the third embodiment shown in FIG. 5 and the fourth embodiment shown in FIG. 6, the vacuum pump 52 communicating with the piping in which the intake pipes are gathered into one is not limited to the above-described embodiment, In order to increase the vacuum capacity, multiple vacuum pumps may be connected in series, or in preparation for an unexpected situation, two vacuum pumps are connected in parallel and either of them can be switched by switching valves. One vacuum pump may be communicated with the pipe. The other is a spare vacuum pump.
[0032]
【The invention's effect】
As described above, since the horizontal shaft pump of the present invention is configured, the following special effects can be obtained.
[0033]
In the horizontal axis pump according to the first aspect, the minimum absolute pressure P2 in the intake pipe can be adjusted by adjusting the pressure regulating valve. And by setting this minimum absolute pressure P2 and the height of the apex of the rising part of the intake pipe as appropriate, the water level rises only halfway through the rising part in the full operation, and water does not flow into the vacuum pump. Therefore, a dry-type vacuum pump can be used, and even if running water is polluted or seawater is mixed, the lifetime of the vacuum pump does not decrease. Moreover, the preceding standby operation can be easily continued. Furthermore, it is possible to easily adjust the minimum absolute pressure P2 in the intake pipe with the pressure adjusting valve.
[0034]
In the horizontal shaft pump according to claim 2, the pump operation can be reliably performed by closing the vacuum shut-off valve immediately before starting the impeller in the preceding standby operation.
[0035]
In the horizontal axis pump according to the third and fourth aspects, the preceding standby operation can be easily continued by appropriately controlling the vacuum cutoff valve and the vacuum pump. Moreover, the power consumption can be reduced by repeating the operation and stop of the vacuum pump as compared with the case where the operation is always continued.
[0036]
In the horizontal axis pump according to claim 5, since a part of the rising portion of the intake pipe has a large diameter and the water storage capacity is increased, the water level in the intake pipe is reduced even if the vacuum pump is stopped in the preceding standby operation. It is gentle and the number of times the vacuum pump is operated is small. Therefore, the power consumption required for starting the vacuum pump can be reduced.
[0037]
In the horizontal axis pump according to the sixth aspect, a plurality of horizontal axis pumps can be set in a preliminary standby operation by a single vacuum pump.
[Brief description of the drawings]
FIG. 1 is an overall configuration diagram of a first embodiment of a horizontal shaft pump according to the present invention.
FIG. 2 is an overall structural diagram of a second embodiment of a horizontal shaft pump according to the present invention.
3 is a longitudinal sectional view of an example of the pressure regulating valve of FIG.
4 is a characteristic diagram showing a minimum absolute pressure in the intake pipe that is adjusted by the pressure regulating valve of FIG. 3; FIG.
FIG. 5 is an overall configuration diagram of a plurality of horizontal shaft pumps according to a third embodiment of the present invention.
FIG. 6 is an overall configuration diagram of a plurality of horizontal shaft pumps according to a fourth embodiment of the present invention.
FIG. 7 is a longitudinal sectional view of a large-diameter portion provided at a rising portion of an intake pipe, showing another structure of the operation stop control of the vacuum pump in the fourth embodiment.
FIG. 8 is an overall structural diagram of an example of a horizontal axis pump having a conventional water filling device.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 10 Pump casing 12 Suction elbow 18 Suction water tank 32 Impeller 38 Opening part 40 Full water detection means 42 Intake pipe 42a Standing part 44 Vacuum shut-off valve 52 Vacuum pump 54 Control means 56 Pressure regulation valve 70 Shut-off valve 72 Large diameter part 74 Upper limit water level detection Means 76 Lower limit water level detection means

Claims

An opening is provided in the upper part of the suction elbow to which the suction pipe suspended from the suction water tank is connected, or the pump casing connected to the suction elbow, or the loose short pipe connected to the pump casing, and one end communicates with the opening. A rising portion is formed in the intake pipe, and a vacuum shut-off valve is interposed in the intake pipe, the other end of the intake pipe is branched into two, one branch is connected to a vacuum pump, and the other branch is A minimum absolute pressure P2 (kPa) in the intake pipe obtained by the vacuum pump by communicating with the pressure regulating valve, and a height h1 (m) from the opening to the top of the rising portion And the height h2 (m) from the highest water level of the suction water tank where the full water operation is performed to the opening, and the height h3 (m) from the lowest water level of the suction water tank where the full water operation is performed to the highest water level in the previous period When ,
h1 + h2> 10− (P2 / 9.8)> h2 + h3
A horizontal axis pump characterized by being configured as follows.

2. The horizontal axis pump according to claim 1, wherein a full water detecting means is provided at the opening, and the vacuum shut-off valve is kept open and the vacuum pump is continuously operated even after full water is detected by the full water detecting means. The horizontal shaft pump is configured to perform the pump operation by closing the vacuum shut-off valve immediately before starting the impeller and performing the standby operation.

The horizontal axis pump according to claim 1, wherein a full water detecting means is provided at the opening, the vacuum shutoff valve is closed after a predetermined time when the full water detecting means detects full water, and the operation of the vacuum pump is stopped, When the water level in the intake pipe is lowered and no full water is detected by the full water detecting means, the vacuum shut-off valve is opened and the operation of the vacuum pump is restarted to continue the preceding standby operation. And horizontal axis pump.

2. The horizontal axis pump according to claim 1, wherein a full water detection means is provided at the opening, an upper limit water level detection means and a lower limit water level detection means are provided at the rising portion of the intake pipe, and the full water detection means detects full water. Further, when the upper limit water level detecting means detects that the water level in the intake pipe has reached the upper limit water level, the vacuum shutoff valve is closed and the operation of the vacuum pump is stopped, and the lower limit water level detecting means is used to stop the inside of the intake pipe. When it is detected that the water level is lower than the lower limit water level, the vacuum shut-off valve is opened and the operation of the vacuum pump is restarted to continue the preceding standby operation.

5. The horizontal axis pump according to claim 4, wherein at least a part of the rising portion of the intake pipe is configured as a large diameter having a large water storage capacity.

A plurality of horizontal axis pumps according to any one of claims 1 to 5 are disposed such that the highest water level and the lowest water level of the suction water tank are the same, and communicated with the respective openings of the plurality of horizontal axis pumps. An abscissa pump characterized in that the intake pipes to be gathered in one pipe are connected to the vacuum pump.