EP0476616A1 - Régulation de commande pour pompes à piston - Google Patents

Régulation de commande pour pompes à piston Download PDF

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Publication number
EP0476616A1
EP0476616A1 EP91115845A EP91115845A EP0476616A1 EP 0476616 A1 EP0476616 A1 EP 0476616A1 EP 91115845 A EP91115845 A EP 91115845A EP 91115845 A EP91115845 A EP 91115845A EP 0476616 A1 EP0476616 A1 EP 0476616A1
Authority
EP
European Patent Office
Prior art keywords
control
valve
piston
pump
pressure
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.)
Ceased
Application number
EP91115845A
Other languages
German (de)
English (en)
Inventor
Alfred Dipl.-Ing. Marian
Hans-Jürgen Pöting
Reinhard Dipl.-Ing. Schwittek
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
PAUL PLEIGER
Original Assignee
PAUL PLEIGER
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by PAUL PLEIGER filed Critical PAUL PLEIGER
Publication of EP0476616A1 publication Critical patent/EP0476616A1/fr
Ceased legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B9/00—Piston machines or pumps characterised by the driving or driven means to or from their working members
    • F04B9/08—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid
    • F04B9/10—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid
    • F04B9/109—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having plural pumping chambers
    • F04B9/117—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having plural pumping chambers the pumping members not being mechanically connected to each other
    • F04B9/1176—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having plural pumping chambers the pumping members not being mechanically connected to each other the movement of each piston in one direction being obtained by a single-acting piston liquid motor
    • F04B9/1178—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having plural pumping chambers the pumping members not being mechanically connected to each other the movement of each piston in one direction being obtained by a single-acting piston liquid motor the movement in the other direction being obtained by a hydraulic connection between the liquid motor cylinders
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B9/00—Piston machines or pumps characterised by the driving or driven means to or from their working members
    • F04B9/08—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid
    • F04B9/10—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid
    • F04B9/103—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having only one pumping chamber
    • F04B9/105—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having only one pumping chamber reciprocating movement of the pumping member being obtained by a double-acting liquid motor
    • F04B9/1056—Piston machines or pumps characterised by the driving or driven means to or from their working members the means being fluid the fluid being liquid having only one pumping chamber reciprocating movement of the pumping member being obtained by a double-acting liquid motor with fluid-actuated inlet or outlet valve
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S417/00—Pumps
    • Y10S417/90—Slurry pumps, e.g. concrete

Definitions

  • the invention relates to a control for piston pumps according to the preamble of claim 1.
  • Piston pumps of this type and in particular double-piston pumps, are used to convey such unusual media as goose feathers, bones, sludges with boulders and the like. It is known to control the hydraulic actuating cylinders for the pump pistons and the hydraulic actuating cylinders for the suction and pressure valves in their staggered work sequence electronically. An electronic control is for certain areas of application, e.g. in a potentially explosive atmosphere, with problems, or not permitted.
  • the invention has for its object to propose a fully hydraulic control for a double-piston pump of the type mentioned, which can also be used in an explosive environment.
  • Fig. 1 and 2 denote the actuating cylinders of a double piston pump, each of which drives a pump piston 3 and 4, respectively.
  • a suction valve 5 and a pressure valve 7 are assigned to the piston 3 and a suction valve 6 and a pressure valve 8 are assigned to the piston 4.
  • These suction and pressure valves are each actuated by an actuating cylinder 9 to 12.
  • S is the suction connection and D the pressure connection of the pump.
  • the two actuating cylinders 1 and 2 are each connected to a changeover valve 13 or 14 in such a way that these changeover valves are switched over in the end positions of the associated pistons 3, 4.
  • the piston of the actuating cylinder can e.g. mechanically engage with a switching element of the changeover valve and adjust it or be mechanically connected to it via a plunger in the end positions.
  • changeover valves 13, 14 are connected via a pressure medium line 37 to a feed pump 35, which supplies a constant pressure P3, and they are connected in FIG. 1 to control devices or main control valves 15, 16, in order to do this as a function of the switching position of the changeover valves switch.
  • a control line 17 leads from the changeover valve 13 and a control line 18 leads from the changeover valve 14 to the two control devices 15 and 16, a manually operable valve 19 being inserted into these two control lines.
  • the two control devices 15, 16 are also connected via pressure medium lines to a supply pump 20, which supplies the pressure medium required to act on the actuating cylinders 1, 2 and the actuating cylinders 9 to 12.
  • the supply pump 20 is pressure and flow controlled, so that it regulates itself automatically to the pressure P1, which is required for the flow in the double piston pump.
  • a pressure medium line 21 leads via a manually controllable valve 22 to the control device 15.
  • From this line 23 leads to the actuating cylinder 2 on the piston side thereof, while the actuating cylinder 2 on the piston rod side is connected via a line 24 to the piston rod side of the actuating cylinder 1, so that when the actuating cylinder 2 is pressurized, the pressure medium on the piston rod side is pressed via the line 24 into the actuating cylinder 1, which thereby executes an opposing stroke.
  • a pressure medium line 25 leads to the control device 15, through which the pressure medium coming from the supply pump 20 is directed with the pressure P1 into the pressure medium line 23 or 25 depending on the switching position, the other line serving as the return line.
  • a return line 26 leads from the control device 15 to a resvervoir 27, the pressure medium line 21 from the supply pump 20 being short-circuited to the return line 26 in the switching position of the manual valve 22 shown.
  • the other control device 16 is also connected to the return line 26 and it is supplied with pressure medium from the supply pump 20 via a line 28, this line 28 branches off from a pressure line 21 and the pressure in this line 28 is reduced to a specific value P2 by a pressure reducing valve 29.
  • a line 31 leads from the control device 16 to the piston side of the actuating cylinders 10 and 11 and to the piston rod side of the actuating cylinders 9 and 12.
  • a line 32 starting from the control device 16 leads to the piston rod side of the actuating cylinders 10 and 11 and to the piston side of the actuating cylinders 9 and 12.
  • a line 33 leads via a manually adjustable valve 34 to the feed pump 35, which supplies pressure medium reduced to, for example, 10 bar via a pressure reducing valve 36, which compensates for any leakage losses and supports the suction stroke on the actuating cylinders 1 and 2 serves.
  • the manual valve 34 shown in FIG. 1 the pressure medium flow from the feed pump 35 is short-circuited with the return line 26.
  • the manual valves 22 and 34 are first brought from the position shown into the other switching position.
  • the actuating cylinders 1 and 2 are then supplied by the supply pump 20 via the manual valve 22 and the control device 15 with pressure medium up to the maximum set pressure, or with the pressure that the medium to be pumped due to its consistency, delivery head, pipe resistance, etc. just needed, with the supply pump 20 automatically adjusting itself to the required pressure.
  • the actuating cylinder 2 e.g. executes a pressure stroke, as indicated by an arrow, the pressure medium displaced on the piston rod side is pressed onto the piston rod side of the actuating cylinder 1, which thus executes a suction stroke which is supported by the pressure supplied by the feed pump 35.
  • the actuating cylinders 9 and 10 of the suction valves 5 and 6 are acted on by the control device 16 such that the suction valve 5 is open and the suction valve 6 is closed, while the pressure valve 7 is closed and the pressure valve 8 is open via the actuating cylinders 11 and 12.
  • the pressure stroke of the actuating cylinder 2 thus pushes the medium to be pumped from the pump piston 4 into the pressure line D, while the pump piston 3 sucks in medium S through the suction connection.
  • the changeover valves 13 and 14 are switched, which in turn switch the control devices 15 and 16 with the aid of the pressure medium flow supplied by the feed pump 35 via the line 37 with a constant value P3, so that the actuating cylinder 1 and 2 perform the reverse strokes and the suction and pressure valves are opened and closed in the reverse manner.
  • the two control devices or main control valves 15 and 16 are provided with latching devices for the switching positions, the latched switching position being maintained until a clear changeover takes place. Should one of the actuating cylinders 1 and 2 reach its end position earlier than the other, and thus already switch the assigned changeover valve while the other changeover valve is still in the previous switch position, then the two control devices 15 and 16 get via the two control lines 17 and 18 switching pressure on both sides, so that there is no clear switching command. The control devices 15 and 16 therefore remain in the previous latched switching position. It is only when the other actuating cylinder has reached its end position and switches the assigned changeover valve that there is a clear switching command to the control devices 15 and 16, which then switch accordingly.
  • the hand valve 22 serves to start and stop the double-piston pump.
  • the direction of movement of the actuating cylinders 1 and 2 and the actuating cylinders 9-12 can be reversed by the manual valve 19. This is especially for revision occasions, repairs and the like of importance.
  • control described can be used advantageously not only for double-piston pumps, but also for simple piston pumps, the piston of the actuating cylinder of this individual pump mechanically switching over the changeover valve, so that the control devices for the changeover of the piston action and the suction and pressure valves only with certainty then switch over when the pump piston has reached its end position.
  • FIG. 2 shows a modified embodiment of the control, the same reference numerals as in FIG. 1 being used for the same or corresponding components.
  • Fig. 2 shows the control in an operating state in which the actuating cylinders 1 and 2 are to move in the direction indicated by arrows, while the associated changeover and control valves are still in the previous switching position and for the direction of actuation indicated by arrows the actuating cylinders are switched Need to become.
  • pilot valves 15 'and 16' are provided in FIG. 2, which are switched over by the changeover valves 13 and 14 via the control lines 17 and 18, these pilot valves 15 'and 16' via one of the feed pump 35 supplied pressure medium line 39 are supplied with a control pressure which is applied by the pilot valves 15 'and 16' to the main control valves 15 and 16 in order to switch them over, so that from these main control valves 15 and 16 the actuating cylinders 1, 2 and the actuating cylinders 9 to 12 be pressurized in the manner described in connection with FIG. 1 or connected to the return line.
  • the manual valve 22 'for starting and stopping the double-piston pump which - as indicated schematically - is provided with latching devices for the two switching positions, is designed in the exemplary embodiment in FIG. 2 as a pilot valve which flows via the pressure medium line 39 from the feed pump 35 at constant pressure is supplied and depending on the manually switched switching position with this pressure switches a main valve 22, via which the main control valves 15 and 16 are supplied with pressure medium from the pump 20 and connected to the return line 26, as is also the case in FIG. 1 is.
  • a pilot valve which flows via the pressure medium line 39 from the feed pump 35 at constant pressure is supplied and depending on the manually switched switching position with this pressure switches a main valve 22, via which the main control valves 15 and 16 are supplied with pressure medium from the pump 20 and connected to the return line 26, as is also the case in FIG. 1 is.
  • the pressure of the feed pump 35 is applied to the left side of the main valve 22 via the manual valve 22 ', which transmits the pressure of the pump 20 to the main control valve 15, which in the position shown actuates the cylinder 1 via the line 25 pressurized with pressure medium, while the actuating cylinder 2 is connected via the line 23 and the main control valve 15 to the return line 26.
  • the main control valve 16 for the actuating cylinders 9 to 12 is supplied with reduced pressure directly by the pump 20 via the line 28, wherein in the switching position shown this pressure, denoted P2, is present on the piston side of the actuating cylinders 9 and 12 and on the piston rod side of the actuating cylinder 11 , while the corresponding actuating pistons are provided with arrows pointing in the subsequent direction of movement after the main control valve 16 has been switched to the other switching position by the pilot valve 16 ', the pilot valve 16' in turn by the changeover valves 13 and 14 via the control lines 17 and 18 is switched, in which the pressure designated P3 of the feed pump 35 is present via line 37, which branches off from line 39.
  • the changeover valves 13 and 14 must be switched from the switch position shown to the other switch position by the mechanical coupling with the pistons 3 and 4 so that the pistons 3 and 4 can carry out the stroke indicated by arrows.
  • the changeover valves 13 and 14 are provided with latching devices for the two switching positions, as indicated schematically.
  • the pilot valves 15 'and 16' are also provided with latching devices in order to hold the switch position concerned until a clear switch command comes from the switch valves 13 and 14 as a function of the end positions of the pistons 3 and 4 .
  • a shuttle valve 40 is arranged, which applies the pressure of the straight pressure line 17 or 18 via a line 41 to a valve 42 in order to switch it over.
  • the pressure P3 of the feed pump 35 is present in the control line 18 via the changeover valve 14, while the control line 17 is connected to the return line 26, so that the valve 42 is in a switching position in which no pressure of the feed pump 35 is present on line 33.
  • the control line 17 carries the pressure P3, while the line 18 is connected to the return line.
  • pilot valves 15 ', 16' and 22 'for switching the associated main valves 15, 16 and 22 serves primarily to control larger amounts of pressure medium on the main valves by means of a smaller amount of pressure medium on the pilot valves, with a constant pressure also being applied to the pilot valves can.
  • FIG. 3 shows a preferred embodiment for a changeover valve 13 or 14, the same reference numerals being used for the same or corresponding components as in FIG. 1 in connection with the actuating cylinder 2.
  • the changeover valve 14 is integrated into a cover 50 of the actuating cylinder 2, the piston 51 of which is firmly connected via the piston rod 52 to the pump piston 4, not shown in FIG. 3.
  • the piston rod 52 is provided along its axis with a blind bore 53, the length of which corresponds approximately to the stroke length of the piston 51 and which serves to receive a shift rod 54.
  • This shift rod 54 is surrounded in the area of the cylinder cover 50 by a pilot sleeve 55 which is displaceable relative to the shift rod 54 and which can be adjusted relative to a control sleeve 57 via annular shoulders 56.
  • the control sleeve 57 is provided on the outer circumference with spaced annular grooves 58, 59 and 60, which are connected via radial bores with associated ring grooves on the inner circumference of the control sleeve.
  • a widened annular groove 61 is formed on the outer circumference of the pilot sleeve 55 and connects the two annular grooves 58 and 59 to one another in the switching position shown, while the annular grooves 59 and 60 are connected to one another in the other switching position.
  • the annular grooves 58, 59 and 60 are connected to the associated lines 37, 18 and 26 in FIG. 1, so that in the switching position shown in FIGS. 1 and 3, the lines 18 and 37 are connected to one another, while the line 26 is blocked on the pilot valve 14 by the pilot sleeve 55.
  • control device 15 can be integrated into the housing of the actuating cylinder 2 according to FIG. 3, for example, by inserting a control slide extending transversely to the line bore 23 into the cylinder cover 50 at 66, which, as indicated in FIG. 1 is acted upon on opposite sides by the pressure of the lines 17 and 18 and thereby controls the pressurization of the lines 23 and 25 according to FIG. 1.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Reciprocating Pumps (AREA)
EP91115845A 1990-09-19 1991-09-18 Régulation de commande pour pompes à piston Ceased EP0476616A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE4029718 1990-09-19
DE4029718A DE4029718C2 (de) 1990-09-19 1990-09-19 Steuerung für eine Kolbenpumpe

Publications (1)

Publication Number Publication Date
EP0476616A1 true EP0476616A1 (fr) 1992-03-25

Family

ID=6414562

Family Applications (1)

Application Number Title Priority Date Filing Date
EP91115845A Ceased EP0476616A1 (fr) 1990-09-19 1991-09-18 Régulation de commande pour pompes à piston

Country Status (3)

Country Link
US (1) US5222872A (fr)
EP (1) EP0476616A1 (fr)
DE (1) DE4029718C2 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1557950A1 (fr) 2004-01-20 2005-07-27 Thales Procédé et dispositif de division de fréquence
WO2013170279A1 (fr) * 2012-05-08 2013-11-14 Jarmo Uolevi Leppanen Système de pompage

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5106272A (en) * 1990-10-10 1992-04-21 Schwing America, Inc. Sludge flow measuring system
DE4127277A1 (de) * 1991-08-17 1993-02-18 Putzmeister Maschf Hydraulische steuerungseinrichtung fuer eine dickstoffpumpe
US5336052A (en) * 1993-04-28 1994-08-09 Abel Pumpen Gmbh & Co. Kg Viscous material pump
DE4403213A1 (de) * 1994-02-03 1995-08-10 Putzmeister Maschf Einrichtung zur Antriebssteuerung einer Zweizylinder-Dickstoffpumpe
DE19716030C1 (de) * 1997-04-17 1998-03-26 Sievers Hans Wilhelm Verfahren zum Betreiben einer Dickstoffkolbenpumpe und Vorrichtung zur Durchführung des Verfahrens
US6779983B1 (en) * 2001-10-05 2004-08-24 David A. Olson Sludge pump with management system
DE102004025910B4 (de) * 2004-05-27 2009-05-20 Schwing Gmbh Antriebseinrichtung für eine Zweizylinderdickstoffpumpe und Verfahren zum Betrieb derselben
US11149725B2 (en) * 2016-01-20 2021-10-19 Weir Minerals Netherlands B.V. Hydraulic pump system for handling a slurry medium

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH224724A (de) * 1941-11-19 1942-12-15 Sulzer Ag Pumpanlage zur Förderung von Flüssigkeiten auf hohen Druck.
US3507347A (en) * 1964-04-14 1970-04-21 Royal Industries Vehicle with pump and remote controlled power take-off
EP0419695A1 (fr) * 1988-06-02 1991-04-03 Takeshi Hoya Dispositif pour le pompage de liquides chargés

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE644378C (de) * 1935-05-12 1937-05-03 I G Farbenindustrie Akt Ges Zweizylindrige Wassersaeulenmaschine mit einer von ihr angetriebenen Kolbenpumpe
US3198123A (en) * 1963-07-16 1965-08-03 Case Co J I Pump and valve assembly
US3234882A (en) * 1964-06-03 1966-02-15 Rexall Drug Chemical Intensifier assembly system and method
US3846049A (en) * 1973-09-24 1974-11-05 Oilgear Co Intensifier pump with half wave modulator
GB1452561A (en) * 1973-11-16 1976-10-13 Fogt Indmasch Apparatus for pumping wet concrete
DE3028396A1 (de) * 1980-07-26 1982-02-11 Wepuko-Hydraulik GmbH & Co Pumpen- und Kompressorenfabrik, 7418 Metzingen Hochdruck-kolbenpumpe

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CH224724A (de) * 1941-11-19 1942-12-15 Sulzer Ag Pumpanlage zur Förderung von Flüssigkeiten auf hohen Druck.
US3507347A (en) * 1964-04-14 1970-04-21 Royal Industries Vehicle with pump and remote controlled power take-off
EP0419695A1 (fr) * 1988-06-02 1991-04-03 Takeshi Hoya Dispositif pour le pompage de liquides chargés

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1557950A1 (fr) 2004-01-20 2005-07-27 Thales Procédé et dispositif de division de fréquence
WO2013170279A1 (fr) * 2012-05-08 2013-11-14 Jarmo Uolevi Leppanen Système de pompage

Also Published As

Publication number Publication date
DE4029718C2 (de) 1995-03-16
US5222872A (en) 1993-06-29
DE4029718A1 (de) 1992-03-26

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