JPH0118273B2

JPH0118273B2 -

Info

Publication number: JPH0118273B2
Application number: JP58060662A
Authority: JP
Inventors: Toshiji Sekimoto
Original assignee: Pacific Machinery and Engineering Co Ltd
Current assignee: Pacific Machinery and Engineering Co Ltd
Priority date: 1983-04-08
Filing date: 1983-04-08
Publication date: 1989-04-05
Also published as: JPS59185881A

Description

【発明の詳細な説明】本発明は、スラリーのような粘性の高い搬送物
を輸送するための往復動複列シリンダ型容積ポン
プの油圧制御装置に関する。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a hydraulic control device for a reciprocating double-row cylinder type positive displacement pump for transporting highly viscous materials such as slurry.

従来のこの型式のポンプおよびこのポンプのた
めの油圧制御装置を第１図に示す。このポンプ
は、ポンプシリンダ１，１′と、ポンプピストン
２，２′と、ピストンロツド３，３′と、吸込弁
４，４′と、吸込弁の作動シリンダ５，５′と、こ
の作動シリンダのピストン６，６′と、吐出弁７，
７′と、吐出弁の作動シリンダ８，８′と、そのピ
ストン９，９′と、ポンプ吐出口１０とを有する。 A conventional pump of this type and a hydraulic control system for this pump are shown in FIG. This pump consists of pump cylinders 1, 1', pump pistons 2, 2', piston rods 3, 3', suction valves 4, 4', working cylinders 5, 5' of the suction valves, and pistons 6, 6', discharge valve 7,
7', an operating cylinder 8, 8' of the discharge valve, its piston 9, 9', and a pump outlet 10.

このポンプシリンダ１と１′には、それぞれ操
作シリンダ１１と１２が連結され、ポンプピスト
ン２と２′にそれぞれ操作ピストン１３と１４が
ピストンロツド３，３′を介して連結されている。
操作シリンダ１１，１２のロツド側端部にはそれ
ぞれパイロツト弁１５，１６が取りつけられ、か
つ反対側端部にはそれぞれ油圧クツシヨン１７，
１８が取りつけられている。周知のパイロツト弁
１５，１６の詳細を第２図に示す。 Operating cylinders 11 and 12 are connected to the pump cylinders 1 and 1', respectively, and operating pistons 13 and 14 are connected to the pump pistons 2 and 2', respectively, via piston rods 3 and 3'.
Pilot valves 15 and 16 are attached to the rod side ends of the operation cylinders 11 and 12, respectively, and hydraulic cushions 17 and 16 are respectively attached to the opposite ends.
18 is installed. Details of a known pilot valve 15, 16 are shown in FIG.

第２図において、１０１は操作シリンダ１１に
取りつけられたハウジングで三つのポートＲ，
Ｓ，Ｗを有する。ハウジング１０１内には弁体１
０３がポートＲを常時閉塞するようにポートＷか
らの圧力油およびばね１０４により付勢されてい
る。 In FIG. 2, 101 is a housing attached to the operating cylinder 11, and has three ports R,
It has S and W. Inside the housing 101 is a valve body 1.
03 is biased by pressure oil from port W and a spring 104 so that port R is always closed.

第１図において、操作弁１９は、スプール２０
と２１をそれぞれ有する操作弁１９Ａと１９Ｂか
らなり、二つの操作弁を連結するライン２４はタ
ンクに、かつライン２５は別置の油圧ユニツトに
接続されている。操作シリンダ１１，１２のピス
トンロツドと反対側端部はそれぞれ操作弁１９の
ポートＢ，Ａに導管２２，２３を介して連結され
ている。一方の操作シリンダ１１のパイロツト弁
１５のポートＳが導管３８を介して操作弁１９Ｂ
のパイロツトポートＨに連結され、かつ他方の操
作シリンダ１２のパイロツト弁１６のポートS′が
操作弁１９Ｂの反対側のパイロツトポートＧに連
結されている。さらに、一方の操作シリンダ１１
のパイロツト弁１５のポートＲが導管３７を介し
て操作シリンダ１１のポートＱに連結され、他方
の操作シリンダ１２のパイロツト弁１６のポート
R′が同様に導管３７′を介して操作シリンダ１２
のポートQ′に連結されている。操作シリンダ１
１の室１１ａと操作シリンダ１２の室１２ａはピ
ストンロツド側で導管４０により相互に連結され
ている。 In FIG. 1, the operation valve 19 is connected to the spool 20.
A line 24 connecting the two operating valves is connected to a tank, and a line 25 is connected to a separate hydraulic unit. Ends of the operating cylinders 11, 12 opposite the piston rod are connected to ports B, A of the operating valve 19 via conduits 22, 23, respectively. Port S of pilot valve 15 of one operating cylinder 11 is connected to operating valve 19B via conduit 38.
and the port S' of the pilot valve 16 of the other operating cylinder 12 is connected to the pilot port G on the opposite side of the operating valve 19B. Furthermore, one operating cylinder 11
The port R of the pilot valve 15 of one is connected to the port Q of the operating cylinder 11 via a conduit 37, and the port of the pilot valve 16 of the other operating cylinder 12 is connected to the port Q of the operating cylinder 11 through a conduit 37.
R' is likewise connected to the operating cylinder 12 via conduit 37'.
is connected to port Q′ of Operation cylinder 1
The chamber 11a of the cylinder 1 and the chamber 12a of the operating cylinder 12 are interconnected by a conduit 40 on the piston rod side.

操作弁１９ＢのポートＣが管路２６，２７を介
して一方の吐出弁７′の作動シリンダ８′のポート
Ｉに連結されていると共に、管路２６，２８を介
して他方の吐出弁７の作動シリンダ８のポートＬ
に連結されている。管路２６は、さらに分岐管路
２８と２９を介して吸込弁４′の作動シリンダ
５′のポートＮに連結され、かつ分岐管路３０を
介して吸込弁４のポートＯに連結されている。ま
た、操作弁１９ＢのポートＤは、管路３１を介し
て吐出弁７の作動シリンダ８のポートＫに連結さ
れていると共に、管路３１と３２を介して吐出弁
７′のポートＪに連結されている。また、管路３
２は、さらに分岐管路３３を介して吸込弁４の作
動シリンダ５のポートＰに連結され、さらに分岐
管路３４を介して吸込弁４′の作動シリンダ５′の
ポートＭに連結されている。他方の操作弁１９Ａ
のパイロツトポートＥは管路３５を介して管路２
６に連結され、かつパイロツトポートＦは管路３
６を介して管路３１に連結されている。 The port C of the operating valve 19B is connected to the port I of the operating cylinder 8' of one discharge valve 7' through conduits 26 and 27, and is connected to the port I of the operating cylinder 8' of the other discharge valve 7 through conduits 26 and 28. Port L of working cylinder 8
is connected to. Line 26 is further connected via branch lines 28 and 29 to port N of actuating cylinder 5' of suction valve 4' and via branch line 30 to port O of suction valve 4. . Further, port D of the operation valve 19B is connected to port K of the operating cylinder 8 of the discharge valve 7 via a conduit 31, and to port J of the discharge valve 7' via conduits 31 and 32. has been done. Also, pipe line 3
2 is further connected to the port P of the working cylinder 5 of the suction valve 4 via a branch line 33, and further connected to the port M of the working cylinder 5' of the suction valve 4' via a branch line 34. . The other operation valve 19A
Pilot port E is connected to pipe 2 via pipe 35.
6, and the pilot port F is connected to conduit 3.
It is connected to the conduit 31 via 6.

第１図において、油圧操作シリンダ１１の操作
ピストン１３が押し行程にあるとき、導管２２の
圧力、いわゆる操作ピストン１３を押している圧
力は、ポンプ吐出口１０にかかる背圧、いわゆる
ポンプピストン２にかかる圧力に対し操作ピスト
ン１３とポンプピストン２のボアー比に比例して
増大する。この実施例の場合、ボアー比は２〜３
となる。例えば、ポンプ吐出口１０にかかる圧力
が100Kgｆ／cm²とすれば、操作ピストン１３にか
かる圧力、従つて導管２２の圧力は200〜300Kg
ｆ／cm²と非常に大きな圧力となつている。 In FIG. 1, when the operating piston 13 of the hydraulic operating cylinder 11 is in its pushing stroke, the pressure in the conduit 22, the so-called pressure pushing the operating piston 13, is reduced by the back pressure on the pump outlet 10, the so-called pump piston 2. The pressure increases in proportion to the bore ratio of the operating piston 13 and the pump piston 2. In this example, the bore ratio is 2-3
becomes. For example, if the pressure applied to the pump outlet 10 is 100 kgf/cm ² , the pressure applied to the operating piston 13, and therefore the pressure in the conduit 22, is 200 to 300 kgf/cm2.
The pressure is extremely large, f/cm ² .

第１図の操作弁１９Ａの位置では、圧力油が管
路２２より操作シリンダ１１に入つてピストン１
３が押し行程を行い、かつ操作シリンダ１２の油
が管路２３よりタンクに戻り、ピストン１４が引
き行程を行つている。また、操作弁１９Ｂの位置
では、管路２６が別置のポンプユニツトに連通
し、かつ管路３１がタンクに連通しているので、
一方のポンプシリンダ１′の吐出弁７′が閉じられ
かつ吸込弁４′が開放されているのに対し、他方
のポンプシリンダ１の吐出弁７が開放されかつ吸
込弁４が閉じられている。操作シリンダ１１のピ
ストン１３がシリンダのポートＱを越えて行程端
に来ると、圧力油が管路３７を経てパイロツト弁
１５に入り、ポートＳより管路３８を経て操作弁
１９ＢのポートＨに入り、スプール２１を押す。
これによつて、操作弁１９Ｂが切換わつて、ポン
プシリンダ１，１′の吸込弁と吐出弁の作動シリ
ンダを含む油圧系統４５の戻り油が管路２６から
タンクに戻ると共に、別置の油圧ユニツトの圧力
油が管路３１を経て油圧系統４５に送られ、吸込
弁と吐出弁用作動シリンダを作動させ、吸込弁と
吐出弁を開閉した後、その背圧が管路３６を経て
他方の操作弁１９Ａのスプール２０を押すので、
操作弁１９Ａが切換わり、圧力油が管路２３を経
て操作シリンダ１２内に入り、ピストン１４が押
し行程を行うと共に、管路２２がタンクに通じる
ので操作シリンダ１１のピストン１３が引き行程
を行う。このとき、操作シリンダ１２の室１２ａ
の油は連結管４０を通つて他方の操作シリンダ１
１の室１１ａに入り、ピストン１３を押す。同時
に、管路３１の圧力油と管路２６の戻り油とによ
りポンプ１の吐出弁７を閉じて吸込弁４を開くと
共に、ポンプ１′の吐出弁７′を開いて吸込弁４′
を閉じる。かくして、ポンプシリンダ１が吸込行
程を行い、ポンプシリンダ１′が押し行程を行う。
以下、これを繰返してポンプシリンダ１，１′が
往復運動を行う。 At the position of the operation valve 19A in FIG. 1, pressure oil enters the operation cylinder 11 from the pipe line 22 and
3 is performing a pushing stroke, the oil in the operating cylinder 12 is returned to the tank through the conduit 23, and the piston 14 is performing a pulling stroke. Furthermore, at the position of the operation valve 19B, the pipe line 26 communicates with the separately placed pump unit, and the pipe line 31 communicates with the tank, so that
The discharge valve 7' of one pump cylinder 1' is closed and the suction valve 4' is open, while the discharge valve 7 of the other pump cylinder 1 is open and the suction valve 4 is closed. When the piston 13 of the operating cylinder 11 reaches the end of its stroke beyond the port Q of the cylinder, pressure oil enters the pilot valve 15 via the line 37, and from port S enters the port H of the operating valve 19B via the line 38. , press the spool 21.
As a result, the operation valve 19B is switched, and the return oil of the hydraulic system 45, which includes the actuation cylinders of the suction valves and discharge valves of the pump cylinders 1 and 1', returns to the tank from the pipe line 26, and the oil from the separate hydraulic Pressure oil from the unit is sent to the hydraulic system 45 through the pipe 31, which operates the actuating cylinders for the suction and discharge valves, opening and closing the suction and discharge valves, and then the back pressure is sent to the other side through the pipe 36. Since the spool 20 of the operating valve 19A is pushed,
The operating valve 19A is switched, pressure oil enters the operating cylinder 12 through the pipe line 23, the piston 14 performs a pushing stroke, and since the pipe line 22 is connected to the tank, the piston 13 of the operating cylinder 11 performs a pulling stroke. . At this time, the chamber 12a of the operation cylinder 12
The oil passes through the connecting pipe 40 to the other operating cylinder 1.
1 enters the chamber 11a and pushes the piston 13. At the same time, the pressure oil in the pipe line 31 and the return oil in the pipe line 26 close the discharge valve 7 of the pump 1 and open the suction valve 4, and at the same time open the discharge valve 7' of the pump 1' and open the suction valve 4'.
Close. Thus, pump cylinder 1 performs a suction stroke and pump cylinder 1' performs a push stroke.
Thereafter, this process is repeated to cause the pump cylinders 1, 1' to reciprocate.

しかしながら、この油圧回路では、例えば、一
方の操作シリンダ１１のピストン１３が第１図の
点線の行程端に来たときに圧力油がシリンダポー
トＱよりパイロツト弁１５に入つてスプリング１
０４に抗して弁体１０３（第２図）を押す。この
弁体１０３は、通常スプリング１０４によりパイ
ロツト弁１５のポートＲを閉じた状態になつてい
る。このスプリング１０４はわずかな圧力差でポ
ートＲが開かないように、ポンプ吐出圧力よりわ
ずかに小さい圧力、従つて非常に大きなスプリン
グ力を生ずるように設定されている。なぜなら、
このときタンク側に通じている操作ピストン１４
のピストンロツドと反対側の圧力はタンクまでの
圧力油損失分のみで約10Kgｆ／cm²位であり、従つ
て操作ピストン１３と１４の間の圧力は10＋数Kg
ｆ／cm²の圧力となり、このような低い圧力でパイ
ロツト弁の弁体１０３が移動して開くようにスプ
リング１０４の力を弱く設定すると、押し行程の
操作ピストン１３がポートＱを通過する前にポー
トＷとＱの間のわずかな圧力差で弁体１０３が浮
動して開いてしまう恐れがあるからである。さ
て、パイロツト弁１５の弁体１０３を通つた圧力
油は、ポートＳから管路３８を経て操作弁１９Ｂ
のパイロツトポートＨを経てスプール２１を押し
て圧力回路の切り換えを行う。スプール２１によ
り押された油（実際にはスプールの移動量は10〜
15mm位である）は、ポートＧを通り、管路３９を
経て移動するが、操作シリンダ１２のパイロツト
弁１６の弁体１０３には、操作シリンダ１２のポ
ートQ′，W′より同等の背圧が来ているので、パ
イロツト弁１６は前述したスプリング１０４′の
大きな設定圧力により完全に閉ざされている。従
つて、管路３９を経て来た圧力油は、パイロツト
弁１６の弁体１０３とこれが嵌合している孔の間
の〓間を通つて逃げる以外は、パイロツト弁１６
と操作弁１９Ｂのスプール２１の間で圧縮されて
切り換わることになる。しかし、前述したように
スプール２１の移動量が実際には小さいから圧力
上昇も小さく、スプリングの設定圧力より大きな
圧力にはならない。次いで、前述したように操作
弁１９Ａのスプール２０が第１図の位置から切り
換わると、操作シリンダ１２の操作ピストン１４
がポンプ圧力を受けかつ操作シリンダ１１の操作
ピストン１３（点線の位置）のピストンロツドと
反対側がタンクに接続されるので、先程まで高圧
のポンプ圧力が働いていた管路３８の圧力が抜か
れて、約10Kgｆ／cm²位の圧力となる。このため、
前述したように圧縮された管路３９の油がその溜
まつていた圧力により操作弁１９Ｂのスプール２
１が急激に押し戻されて、操作弁切り換え用の回
路が動作不良となる。すなわち、ピストン速度が
比較的遅い場合は、パイロツト弁の〓間からの逃
げ、または油圧回路のホースの膨張などによつて
圧力上昇を吸収しえるが、ピストン速度が速くな
ると、この吸収力が小さくなり、次のような現
象、すなわち、１管路３９の圧力上昇によるサージ圧の発生、２圧力上昇の反復による振動、ホース類の損
傷、回路の寿命の低下、３操作弁１９Ａ，１９Ｂのスプールの誤動作、
これによりピストンストロークの動作不良など
が発生する。 However, in this hydraulic circuit, for example, when the piston 13 of one operating cylinder 11 reaches the stroke end indicated by the dotted line in FIG.
04 and press the valve body 103 (FIG. 2). This valve body 103 is normally in a state in which port R of the pilot valve 15 is closed by a spring 104. This spring 104 is set to generate a pressure slightly lower than the pump discharge pressure, and therefore a very large spring force, so that the port R will not open due to a slight pressure difference. because,
At this time, the operating piston 14 communicating with the tank side
The pressure on the opposite side of the piston rod is approximately 10 kgf/ ^cm2 due to pressure oil loss up to the tank, and therefore the pressure between the operating pistons 13 and 14 is 10 + several kg.
f/cm ² , and if the force of the spring 104 is set weakly so that the valve body 103 of the pilot valve moves and opens at such a low pressure, the force of the spring 104 is set weakly. This is because a slight pressure difference between ports W and Q may cause the valve body 103 to float and open. Now, the pressure oil that has passed through the valve body 103 of the pilot valve 15 flows from the port S through the conduit 38 to the operation valve 19B.
Press the spool 21 through the pilot port H to switch the pressure circuit. Oil pushed by spool 21 (actually, the amount of movement of the spool is 10~
(approximately 15 mm) passes through port G and moves through conduit 39, but the valve element 103 of pilot valve 16 of operating cylinder 12 receives an equal back pressure from ports Q' and W' of operating cylinder 12. , the pilot valve 16 is completely closed by the large set pressure of the spring 104'. Therefore, the pressure oil that has passed through the pipe line 39 escapes from the pilot valve 16 except through the gap between the valve element 103 of the pilot valve 16 and the hole in which it is fitted.
and the spool 21 of the operating valve 19B and are switched. However, as described above, since the amount of movement of the spool 21 is actually small, the pressure rise is also small, and the pressure does not exceed the set pressure of the spring. Next, as described above, when the spool 20 of the operating valve 19A is switched from the position shown in FIG.
receives pump pressure, and the opposite side of the piston rod of the operating piston 13 of the operating cylinder 11 (position indicated by the dotted line) is connected to the tank, so the pressure in the pipe line 38, where the high pump pressure was applied until now, is released, and approximately The pressure is about 10Kgf/ ^cm2 . For this reason,
As mentioned above, the oil in the compressed pipe line 39 is compressed by the accumulated pressure in the spool 2 of the operating valve 19B.
1 is suddenly pushed back, causing the operating valve switching circuit to malfunction. In other words, when the piston speed is relatively slow, the pressure increase can be absorbed by escape from the pilot valve or by expansion of the hose in the hydraulic circuit, but as the piston speed increases, this absorption force decreases. The following phenomena occur: 1. Generation of surge pressure due to pressure increase in the pipe line 39, 2. Vibration due to repeated pressure increase, damage to hoses, shortened life of the circuit, 3. Spools of operating valves 19A, 19B. malfunction,
This causes malfunction of the piston stroke.

本発明の目的は、上記の欠点を除去して、両方
の操作シリンダのピストンをその行程端位置まで
確実に作動させるとともに、吸込弁ならびに吐出
弁の切換を確実に行なうことができ、サージ圧の
発生を防ぎ、各部の寿命を長くすることができる
往復動複列シリンダ型容積ポンプの油圧制御装置
を提供することである。 An object of the present invention is to eliminate the above-mentioned drawbacks, to ensure that the pistons of both operating cylinders are operated to their stroke end positions, to ensure reliable switching of the suction and discharge valves, and to reduce surge pressure. It is an object of the present invention to provide a hydraulic control device for a reciprocating double-row cylinder type positive displacement pump that can prevent the occurrence of such problems and extend the life of each part.

以下、本発明の実施例を第３図により説明す
る。第３図において第１図と同じ部品には同じ符
号を付してある。 Hereinafter, an embodiment of the present invention will be described with reference to FIG. In FIG. 3, the same parts as in FIG. 1 are given the same reference numerals.

本発明により、一方の操作シリンダ１１の押し
行程端位置と引き行程端位置の両方にそれぞれパ
イロツト弁１５′と１６′を取りつけてある。 According to the invention, pilot valves 15' and 16' are installed at both the push stroke end position and the pull stroke end position of one operating cylinder 11, respectively.

本発明に使用するパイロツト弁を第４図に示
す。第４図において１０１′は操作シリンダ１１
に取りつけられたハウジングで、三つのポート
Ｒ，Ｓ，Ｗを有する。１０２′はハウジング１０
１′内の孔に挿入されたパイロツトガイドで、ポ
ートＲ，Ｓに連通する孔を有する。パイロツトガ
イド１０２′内には弁体１０３′がポートＲを常時
閉塞するようにポートＷからの圧油およびばね１
０４′により付勢されている。これにより操作シ
リンダ１１は両行程端位置まで運動する。 A pilot valve used in the present invention is shown in FIG. In Fig. 4, 101' is the operating cylinder 11.
The housing is attached to the housing and has three ports R, S, and W. 102' is the housing 10
A pilot guide is inserted into a hole in 1' and has holes communicating with ports R and S. Inside the pilot guide 102', pressure oil from the port W and a spring 1 are supplied so that the valve body 103' always closes the port R.
04'. This causes the operating cylinder 11 to move to both stroke end positions.

また、パイロツト操作弁１５′のポートＳは管
路３８を介して操作弁１９Ｂの一方のパイロツト
ポートＨに連結されていると共に、パイロツト操
作弁１６′の出口側ポートS′が管路４１を介して
同じ操作弁１９Ｂの反対側のパイロツトポートＧ
に連結されている。そして、本発明により、操作
弁１９ＢのパイロツトポートＨからの管路３８
は、さらに分岐管路４２を経て操作シリンダ１９
ＡのポートＢに連結され、操作弁１９Ｂのパイロ
ツトポートＧからの管路４１が分岐管路４３を経
て操作弁１９ＡのポートＡに連結されている。な
お４４は逆止弁を示す。これによつて、操作シリ
ンダ１１のピストン１３が押し行程で点線の行程
端位置に来て、操作シリンダ１１内の圧力油がシ
リンダのポートＱよりパイロツト弁１５のポート
Ｒ，Ｓを経て管路３８を通り、操作弁１９Ｂのパ
イロツトポートＨでスプール２３を押したとき
に、スプール２３の反対側に充満している油がポ
ートＧより管路４１，４３を通り、さらに逆止弁
４４を経て操作弁１９ＡのポートＡ−Ｔを通り、
タンクに戻ることができる。操作弁１９Ｂのスプ
ール２３が第３図と反対側の位置にあつて、操作
シリンダ１１のピストン１３が引き行程端位置に
来たときにも同様にスプール２３の移動によりパ
イロツトポートＨから出る操作弁１９Ｂ内の油を
管路３８，４２、逆止弁４４、操作弁１９Ａのポ
ートＢ−Ｔ（このとき操作弁１９Ａのスプールも
第３図と反対側の位置にある）からタンクに戻す
ことができる。 Further, the port S of the pilot operating valve 15' is connected to one pilot port H of the operating valve 19B via a conduit 38, and the outlet side port S' of the pilot operating valve 16' is connected via a conduit 41. pilot port G on the opposite side of the same operation valve 19B.
is connected to. According to the present invention, the pipe line 38 from the pilot port H of the operating valve 19B
further passes through the branch pipe 42 to the operating cylinder 19.
A pipe line 41 from pilot port G of the operating valve 19B is connected to port A of the operating valve 19A via a branch pipe line 43. Note that 44 indicates a check valve. As a result, the piston 13 of the operating cylinder 11 comes to the stroke end position indicated by the dotted line during the pushing stroke, and the pressure oil in the operating cylinder 11 flows from the port Q of the cylinder through the ports R and S of the pilot valve 15 to the pipe line 38. When the spool 23 is pushed by the pilot port H of the operating valve 19B, the oil filling the opposite side of the spool 23 passes through the pipes 41 and 43 from the port G, and then passes through the check valve 44 before being operated. Pass through port A-T of valve 19A,
You can return to the tank. When the spool 23 of the operation valve 19B is in the opposite position to that shown in FIG. 3 and the piston 13 of the operation cylinder 11 reaches the end of the retracting stroke, the operation valve exits from the pilot port H due to the movement of the spool 23. The oil in 19B can be returned to the tank through the pipes 38, 42, the check valve 44, and the port B-T of the operating valve 19A (at this time, the spool of the operating valve 19A is also in the opposite position as in Fig. 3). can.

他方の操作シリンダ１２のピストン１４の押し
行程端位置と引き行程端位置にそれぞれクツシヨ
ン弁１７と１８を設けるのが望ましい。クツシヨ
ン弁１７と１８は、ピストン１４が押し行程にあ
るときに、その行程端直前で操作シリンダ１２の
一方の室１２ｂが油圧クツシヨン弁１７のポート
Ｕ−Ｖを介して反対側の室１２ａと連通して室１
２ｂから圧力油が１２ａに流れ、クツシヨン作用
をすると共に、室１２ａ−連結管４０−室１１ａ
内の油の不足分を補給するのに役立つ。また、引
き行程のためのクツシヨン弁１８は、ピストン１
４の引き行程端直前で操作シリンダ１２の一方の
室１２ａから圧力油がクツシヨン弁１８のポート
U′−V′を介して反対側の室１２ｂに流入してク
ツシヨン作用をすると共に、室１２ａ−連結管４
０−室１１ａ内の油の過多分を抜き出すのに役立
つ。 It is desirable to provide cushion valves 17 and 18 at the end of the pushing stroke and the end of the pulling stroke of the piston 14 of the other operating cylinder 12, respectively. The cushion valves 17 and 18 are configured so that when the piston 14 is in the pushing stroke, one chamber 12b of the operating cylinder 12 communicates with the opposite chamber 12a via the port U-V of the hydraulic cushion valve 17 just before the end of the stroke. Room 1
Pressure oil flows from 2b to 12a and acts as a cushion, and also connects chamber 12a-connecting pipe 40-chamber 11a.
Helps replenish the lack of oil in the body. Further, the cushion valve 18 for the pulling stroke is connected to the piston 1.
4, just before the end of the pulling stroke, pressure oil flows from one chamber 12a of the operating cylinder 12 to the port of the cushion valve 18.
It flows into the chamber 12b on the opposite side via U'-V' and acts as a cushion, and the chamber 12a-connecting pipe 4
It serves to extract excess oil in the 0-chamber 11a.

さらに、本発明により、操作弁１９Ｂのポート
ＣおよびＤを、それぞれ、ポンプの吸込弁４，
４′および吐出弁７，７′の作動シリンダ５，５′
および８，８′を含む油圧系統４５に連結する二
本の管路２６および３１にそれぞれ減圧弁４６が
取りつけられている。 Further, according to the present invention, ports C and D of the operation valve 19B are connected to the suction valve 4 of the pump, respectively.
4' and the operating cylinders 5, 5' of the discharge valves 7, 7'.
A pressure reducing valve 46 is attached to each of the two pipe lines 26 and 31 connected to the hydraulic system 45 including the pipes 8 and 8'.

ポンプ１，１′により搬送される物の性状およ
び移送用管路の径や長さなどにより、操作シリン
ダ１１，１２に必要な油圧力が異なつてくる。第
１図の従来技術のように減圧弁４６がない場合に
は、別置の油圧ユニツトからの圧力油により操作
弁１９、操作シリンダ１１，１２、吸込弁および
吐出弁用作動シリンダ５，５′，８，８′に全て同
等な圧力が加わつているので、前述の種々の条件
により操作シリンダ１１，１２のピストン１３，
１４を押すための必要圧力が高くなつてくると、
吸込弁４，４′および吐出弁７，７′を切換える圧
力も高くなる。これらの吸込弁や吐出弁は一分間
に数回〜十数回切換わり、その都度金属面同志が
接触するので、圧力が高くなると摩耗も大きくな
る。しかしながら、本発明により減圧弁４６を取
りつけると、操作シリンダ１１，１２に必要な圧
力が高くなつた場合でも、減圧弁４６の設定圧力
より高い圧力が吸込弁５，５′および吐出弁７，
７′に加えられず、これらの弁を保護することが
できる。 The hydraulic pressure required for the operating cylinders 11, 12 varies depending on the properties of the objects to be transported by the pumps 1, 1' and the diameter and length of the transport pipe. In the case where there is no pressure reducing valve 46 as in the prior art shown in FIG. 1, pressure oil from a separate hydraulic unit is used to operate the operation valve 19, operation cylinders 11, 12, suction valve and discharge valve operation cylinders 5, 5'. , 8, 8', the pistons 13, 13 of the operating cylinders 11, 12 are affected by the various conditions mentioned above.
As the pressure required to press 14 increases,
The pressure for switching the suction valves 4, 4' and the discharge valves 7, 7' also increases. These suction valves and discharge valves are switched several to ten-odd times per minute, and the metal surfaces come into contact with each other each time, so as the pressure increases, the wear increases. However, when the pressure reducing valve 46 is installed according to the present invention, even if the pressure required in the operating cylinders 11, 12 becomes higher, the pressure higher than the set pressure of the pressure reducing valve 46 will be applied to the suction valves 5, 5' and the discharge valve 7,
7' to protect these valves.

また、ポンプの吸込弁４，４′および吐出弁７，
７′は、搬送物の通路を閉じるときに搬送物の逆
流を防ぐために迅速な運動を必要とするが、開動
作のときにはそれほど迅速な運動を必要としな
い。従つて、本発明により、吸込弁および吐出弁
の作動シリンダ５，５′，８，８′のピストンロツ
ド側端部のポートＮ，Ｐ，Ｊ，Ｌに連結される油
圧管路にそれぞれ絞り弁４７を設けることによ
り、開動作での吸込弁および吐出弁の動きを遅く
して、吸込弁と吐出弁のピストン６，６′，９，
９′のピストン、およびこれらのピストンが当る
作動シリンダ５，５′，８，８′の部分を保護する
ことができる。 In addition, the pump's suction valves 4, 4' and discharge valves 7,
7' requires a rapid movement when closing the conveyed article passage to prevent the reverse flow of the conveyed article, but does not require such rapid movement during the opening operation. Therefore, according to the invention, throttle valves 47 are provided in the hydraulic lines connected to the ports N, P, J, L at the ends of the piston rod side of the actuating cylinders 5, 5', 8, 8' of the suction and discharge valves, respectively. By providing the pistons 6, 6', 9,
The pistons 9' and the parts of the working cylinders 5, 5', 8, 8' against which these pistons rest can be protected.

本発明では、一方の操作シリンダの押し行程端
位置と引き行程端位置にそれぞれパイロツト弁を
取りつけると共に、操作シリンダ用の他方の操作
弁の二つのポートにそれぞれポンプシリンダ用の
一方の操作弁のパイロツトポートを逆止弁を介し
て接続し、この逆止弁を、操作シリンダ用の他方
の操作弁のポートに向かう方向にのみ油が流れる
ように設けたので、一方の操作シリンダの行程端
でパイロツト弁が開いて圧力油がポンプシリンダ
用の一方の操作弁のパイロツトポートに流れてス
プールを押したときに、この一方の操作弁のスプ
ールの反対側の室を充満しているパイロツト油が
ただちに逆止弁を通つて操作シリンダ用の他方の
操作弁よりドレン側に戻される。その結果操作弁
の切換えが円滑に行われるので、両操作シリンダ
のピストンが両行程端位置まで確実に作動すると
共に、吸込弁と吐出弁の切換も確実に行われ、さ
らに従来発生していたサージ圧も発生しないので
各部品の寿命が長くなる等の多大の利点がある。 In the present invention, a pilot valve is installed at each of the push stroke end position and the pull stroke end position of one operation cylinder, and the pilot valve of one operation valve for the pump cylinder is attached to two ports of the other operation valve for the operation cylinder. The ports are connected via a check valve, and this check valve is installed so that oil flows only in the direction toward the port of the other operating valve for the operating cylinder. When the valve opens and pressure oil flows into the pilot port of one operating valve for the pump cylinder and pushes the spool, the pilot oil filling the chamber on the opposite side of the spool of this one operating valve immediately reverses. It passes through the stop valve and is returned to the drain side from the other operating valve for the operating cylinder. As a result, the operating valves are switched smoothly, so the pistons of both operating cylinders operate reliably to both stroke end positions, and the suction and discharge valves are also switched reliably. Since no pressure is generated, there are many advantages such as a longer lifespan for each component.

[Brief explanation of drawings]

第１図は往復動複列シリンダスラリーポンプの
ための従来の油圧制御回路を示す図、第２図は操
作シリンダの行程端位置で操作弁を切換えるため
に操作シリンダの行程端位置に取りつけられる公
知のパイロツト弁の詳細断面図、第３図はスラリ
ーポンプのための本発明による油圧制御回路を示
す図、第４図は本発明の油圧制御回路で操作シリ
ンダに取りつけられるパイロツト弁の詳細断面図
である。１，１′……ポンプシリンダ、４，４′……吸込
弁、５，５′；８，８′……作動シリンダ、７，
７′……吐出弁、１１……一方の操作シリンダ、
１２……他方の操作シリンダ、１５′，１６′……
パイロツト弁、１７，１８……クツシヨン弁、１
９……操作弁、４６……減圧弁、４７……絞り
弁。 FIG. 1 shows a conventional hydraulic control circuit for a reciprocating double-row cylinder slurry pump, and FIG. 2 shows a conventional hydraulic control circuit installed at the end-of-stroke position of the operating cylinder to switch the operating valve at the end-of-stroke position of the operating cylinder. FIG. 3 is a diagram showing a hydraulic control circuit according to the present invention for a slurry pump; FIG. 4 is a detailed cross-sectional view of a pilot valve attached to an operating cylinder in the hydraulic control circuit according to the present invention. be. 1, 1'... Pump cylinder, 4, 4'... Suction valve, 5, 5'; 8, 8'... Working cylinder, 7,
7'...Discharge valve, 11...One operating cylinder,
12...Other operating cylinder, 15', 16'...
Pilot valve, 17, 18...Cushion valve, 1
9...operation valve, 46...pressure reducing valve, 47...throttle valve.

Claims

[Claims] 1. Two operating cylinders 11 and 12 each connected in series to two pump cylinders for pumping a highly viscous material and connected to each other; one operating valve 19B for the pump cylinder, which has pilot valves 15', 16', pilot ports H, G connected to the output ports S, S' of these pilot valves by conduits, and the operating cylinder 11; ,1
and the other operating valve 19A for the operating cylinder having two ports A and B connected to the operating valve 19B by a conduit, and the two ports C and D of one operating valve 19B.
are connected to a hydraulic system 45 including operating cylinders for the suction valves 4, 4' and the discharge valves 7, 7' of the two pump cylinders 1, 1', respectively, and when the piston of the operating cylinder reaches the end of its stroke, the pilot A reciprocating double-row cylinder type in which the valve is opened by pressure oil on the pushing side of the piston in the operating cylinder, and the pressure oil acts on the pilot port G or H of one operating valve 19B to switch that operating valve. In a hydraulic control device for a positive displacement pump, pilot valves 15' and 16' are installed at the push stroke end position and pull stroke end position of one operation cylinder 11, respectively, and two ports A and B of the other operation valve 19A are installed.
The pilot ports H and G of one of the operating valves 19B are connected to each other via check valves 44, and the check valves are arranged so that oil flows only in the direction toward the ports A and B of the other operating valve 19A. A device characterized in that: 2. Two operating cylinders 11 and 12 each connected in series to two pump cylinders for pressure-feeding a highly viscous material and interconnected, and a pilot valve 15' installed at the stroke end position of the operating cylinder. 16', one operating valve 19B for the pump cylinder having pilot ports H, G connected to the output side ports S, S' of these pilot valves by conduits, and said operating cylinders 11, 1.
and the other operating valve 19A for the operating cylinder having two ports A and B connected to the operating valve 19B by a conduit, and the two ports C and D of one operating valve 19B.
are connected to a hydraulic system 45 that includes actuating cylinders for the suction valves 4, 4' and the discharge valves 7, 7' of the two pump cylinders 1, 1', respectively;
Pilot valves 15' and 16' are installed at the pushing stroke end position and the pulling stroke end position of 1, respectively, and
Pilot port G of one operating valve 19B is connected to two ports A and B of the other operating valve 19A, respectively.
H is connected via a check valve 44, and the check valve is provided so that oil flows only in the direction toward ports A and B of the other operating valve 19A. In hydraulic control equipment,
One operation valve 19B is connected to the pump cylinders 1, 1'
Actuation cylinders 5, 5'; 8, suction and discharge valves;
A pressure reducing valve 46 is installed in the hydraulic line 45 connected to the hydraulic system 45 including the suction valve and the discharge valve, even if high pressure is applied to the operating cylinder hydraulic system. A device characterized in that it does not apply high pressure. 3. Two operating cylinders 11, 12 each connected in series to two pump cylinders for pumping a highly viscous material and interconnected, and a pilot valve 15' installed at the stroke end position of the operating cylinder. 16', one operating valve 19B for the pump cylinder having pilot ports H, G connected to the output side ports S, S' of these pilot valves by conduits, and said operating cylinders 11, 1.
and the other operating valve 19A for the operating cylinder having two ports A and B connected to the operating valve 19B by a conduit, and the two ports C and D of one operating valve 19B.
are connected to a hydraulic system 45 that includes actuating cylinders for the suction valves 4, 4' and the discharge valves 7, 7' of the two pump cylinders 1, 1', respectively;
Pilot valves 15' and 16' are installed at the pushing stroke end position and the pulling stroke end position of 1, respectively, and
The pilot port H of one operating valve 19B is connected to the two ports A and B of the other operating valve 19A, respectively.
G is connected via a check valve 44, and the check valve is provided so that oil flows only in the direction toward ports A and B of the other operating valve 19A. In hydraulic control equipment,
operating cylinders 5, 5' of each suction and discharge valve;
The apparatus is characterized in that a throttle valve 47 is provided in each of the hydraulic lines connected to the piston rod side ends of piston rods 8 and 8', thereby preventing damage to the valve bodies of the suction valve and the discharge valve.