EP0402390A1 - Agencement de commande de pompes a double cylindre pour liquides epais. - Google Patents

Agencement de commande de pompes a double cylindre pour liquides epais.

Info

Publication number
EP0402390A1
EP0402390A1 EP89903132A EP89903132A EP0402390A1 EP 0402390 A1 EP0402390 A1 EP 0402390A1 EP 89903132 A EP89903132 A EP 89903132A EP 89903132 A EP89903132 A EP 89903132A EP 0402390 A1 EP0402390 A1 EP 0402390A1
Authority
EP
European Patent Office
Prior art keywords
valve
pressure
cylinders
cylinder
control arrangement
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP89903132A
Other languages
German (de)
English (en)
Other versions
EP0402390B1 (fr
Inventor
Rolf Dose
Hartmut Benckert
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.)
Putzmeister Concrete Pumps GmbH
Original Assignee
Putzmeister Werk Maschinenfabrik GmbH
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 Putzmeister Werk Maschinenfabrik GmbH filed Critical Putzmeister Werk Maschinenfabrik GmbH
Publication of EP0402390A1 publication Critical patent/EP0402390A1/fr
Application granted granted Critical
Publication of EP0402390B1 publication Critical patent/EP0402390B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

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
    • 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 arrangement for a two-cylinder slurry pump of the type specified in the preamble of claim 1.
  • Thick matter pumps of this type have two delivery cylinders which can be actuated in a push-pull manner by hydraulic drive cylinders and open into a material feed container, the delivery pistons of which are connected to the pistons of the drive cylinder via a common piston rod and the openings on the container side during the pressure stroke by means of at least one hydrozy ⁇ easier swiveling pipe switch can be connected to a conveyor line and are open to the inside of the container during the suction stroke.
  • the drive cylinders are alternately subjected to high and low pressure at one end in accordance with the position of a reversing valve via a hydraulic pump, while at the other end they are hydraulically connected to one another.
  • the reversing valve is actuated each time the end positions of the pistons in the delivery cylinders and / or in the drive cylinders are reached so that the hydraulic supply to the drive cylinders and to the hydraulic cylinder actuating the pipe switch is reversed together.
  • a pressure compensation line which includes a check valve and bridges the drive piston in its end positions, at the two ends of one of the two drive cylinders.
  • the object of the invention is to create a control arrangement for two-cylinder thick matter pumps with which a large variation in the delivery quantity is possible and nevertheless a stroke correction is ensured without a piston stop.
  • the invention is based on the knowledge that when a combination of two position signals is triggered to trigger the reversal, one of which ensures a reliable changeover especially in the low-load range and the other, especially in the high-load range, a reliable smooth reversal with Stroke correction can be achieved in a wide range of flow rates.
  • a pressure switching valve for actuating the reversing valve in one and the other direction is connected to the drive cylinder, which has no pressure compensation lines, at least at a distance from the drive piston length of the two ends thereof, while on the rod side End of the feed cylinder
  • an electrical switching arrangement which responds to trigger elements fixed to the rod is provided, with which the reversing valve can be actuated in parallel with the pressure switching valves.
  • the electrical switching arrangement has a sequence control which acts alternately on one and the other actuating side of the reversing valve, preferably in the form of a step relay, wherein two proximity switches, each responding to one of the rigid trigger elements, are expediently provided.
  • the reversing valve can be acted upon by the control pressure on the input side via a servo valve, while a bypass valve which can be controlled by the electrical switching arrangement against the force of a spring is additionally arranged parallel to the servo valve.
  • the bypass valve serves to increase the control pressure and volume flow at the moment of reversal, so that the pilot pressure behind the reversing valve is increased to the maximum pressure independently of the preselected control pressure at the servo valve.
  • the reversal of direction of the reversing sier-Hydropu pe accelerates.
  • a pressure switch is provided for blocking the electrical changeover signals when a high pressure setpoint is exceeded in the drive cylinders.
  • the single figure shows a circuit diagram of a control arrangement for a two-cylinder thick matter pump.
  • the thick matter pump essentially consists of two delivery cylinders 60, the end openings of which open into a material feed container (not shown) and can be connected alternately to a delivery line 51 via a pipe switch 50 during the pressure stroke.
  • the delivery cylinders 60 are driven in a push-pull manner via hydraulic drive cylinders 13, 14 and the reversing hydraulic pump 2 designed as a swash plate axial piston pump in the exemplary embodiment shown.
  • the delivery pistons 61 are connected to the pistons 63 of the drive cylinders 13 and 14 via a common piston rod 62.
  • the drive cylinders 13, 14 are pressurized with pressure oil at the bottom via the pressure lines 7 and 8 with the aid of at least one swash plate axial piston pump 2 and are hydraulically connected to one another at their rod-side end via a cross line 65.
  • a pressure equalization line 81 which bridges the relevant drive piston 63 and contains a check valve 80, is arranged at the two ends of the drive cylinder 13.
  • the direction of movement of the pistons 63 in the drive cylinders 13 and 14 is reversed in that the swash plate 3 of the axial piston pump 2 swings through the zero position triggered by a reversing signal and thus changes the direction of delivery of the oil in the lines 7 and 8 in the free flow.
  • the axial piston pump 2 works in a closed circuit and is supplied with sufficient preload by a feed pump 6, which is limited by a low-pressure relief valve 45.
  • the delivery rate of the axial piston pump 2 is defined by the swivel angle of the swash plate 3 at a predetermined drive speed. The swash plate angle and thus the delivery rate can be adjusted in proportion to a control pressure which actuates the proportional valve 10 via the lines 11 or 12.
  • the control pressure can be set as a setpoint, for example, from a control room via an electrically operated servo or proportional valve 29.
  • the servo valve 29 not only regulates the control pressure.
  • a bypass valve 31 is connected in parallel with the servo valve 29, which allows a sufficient amount of oil into the line 30 on the servo valve 29 during the changeover phase. This is the only way to quickly reverse the thick matter pump with the pipe switch.
  • control oil is passed through the both electrically and hydraulically actuated reversing valve 21 and the downstream reversing valve 34 either to line 12 or to line 11 and thus causes the axial piston pump 2 to be reversed.
  • the reversing valve 21 is actuated once hydraulically via the lines 19 and 20 with the aid of the switching valves 15 and 16 arranged in front of the two end positions of the piston 63 on the drive cylinder 14.
  • the piston 63 reaches its switching positions, the pressure difference switches between the lines 17 and 18 around the valve 15 or 16, the control line 19 or 20 alternately becoming pressurized or depressurized.
  • the reversing valve 21 is actuated via the control lines 19 and 20 and engages in the respective end position.
  • the valve 21 is reversed, the control pressure is reversed in lines 11 and 12 and in parallel in lines 37 and 38; Switch over the thick matter pump.
  • the pressure difference for the hydraulic switching of the valves 15 and 16 must first be built up for their switching through. When idling, this takes place only in the end position of the pistons 63. If the machine is running fast at the same time, undesirable hard blows of the piston against the cylinder base or the cylinder cover occur. In addition to the mechanical stresses, this results in high hydraulic pressure peaks, additional oil heating and an undesired interruption in delivery in the thick material. If, on the other hand, there is a certain pressure level and thus a sufficiently large pressure difference between the lines 17 and 18, the reversing pulse runs through the lines 19 and 20 quickly enough without the pistons 63 mechanically striking the cylinders 13 and 14.
  • an electrical control is provided in parallel with the hydraulic actuation of the reversing valve 21, which is carried out via the electrical proximity switches 24 and 25 in the area of the water tank 64.
  • the proximity switches 24 and 25 are triggered via switch heads 22 and 23, which are arranged on the piston rods 62 in the vicinity of the delivery piston 61.
  • the switches 24 and 25 can be moved relative to the end position of the switch heads 22 and 23, so that the time of the triggering electrical pulse can be preselected within certain limits.
  • the pulses of the switches 24 and 25 are expediently passed to the electrical actuation inputs of the reversing valve 21 via a step relay (not shown). At the same time, the high pressure in the.
  • the pressure switch 27 is adjusted so that the reversing of the reversing valve 21 takes place exclusively electrically via the switches 24 and 25 when the pressure falls below a predetermined minimum pressure.
  • the reversal then takes place exclusively via the hydraulic pulses from the switching valves 15 and 16.
  • the safety valve 36 which is actuated in parallel with the pressure switch 27, is pilot-controlled by the high pressure and results in a pressure cutoff in the high pressure system. After reaching the pressure value set there, the pump 2 switches to compensation circuit, ie the swivel angle is reduced because the control pressure drops.
  • the switches 24 and 25 trigger a bypassing of the bypass valve 31.
  • the bypass valve 31 serves to increase the control pressure and volume flow at the moment of reversal. The reversal is triggered when one of the two proximity switches 24 or 25 is activated by the associated switching head 22 or 23. At this moment the valve 31 is electrically switched through, so that the full pressure of the feed pump 6 passes behind the proportional valve 29 via an adjustable throttle 33. Regardless of the electrically preselected control pressure at valve 29, the pilot pressure behind valve 21 is increased. This means that there is sufficient oil for the pilot control of the reversing valve 39 for switching through the one connected to the pipe switch 50 which hydraulic cylinders 42 are available.
  • valve 31 drops to normal position when there is no signal from electrical switches 24 or 25.
  • the two 4/2 valves 34 and 35 are necessary if the thick matter pump is to be returned, i.e. Sucking from the delivery line 51 is switched. In this case, for reasons of control logic, on the one hand the hydraulic signal from the two switching valves 15 and 16 and on the other hand the signal directed to the hydraulic proportional valve 10 must be reversed.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Reciprocating Pumps (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

Un agencement de commande est destiné à des pompes à double cylindre pour liquides épais comprenant deux cylindres d'alimentation (60) actionnables symétriquement par des cylindres hydrauliques d'actionnement (13, 14) et s'ouvrant dans un récipient distributeur de matériau. Pendant la course de pression, les ouvertures des cylindres d'alimentation (60) côté récipient peuvent être reliées à un conduit d'alimentation (42) par un tuyau d'aiguillage (50) pivotable au moyen d'au moins un cylindre hydraulique (42), et pendant la course d'aspiration, les ouvertures sont en communication avec l'intérieur du récipient. L'agencement de commande comprend une soupape d'inversion (21) actionnable afin d'inverser conjointement l'amenée d'huile de commande vers le cylindre hydraulique (42) d'actionnement du tuyau d'aiguillage (50) et vers une pompe réversible (2) d'une installation hydraulique à flux libre qui commande les cylindres d'actionnement (13, 14), lorsque les pistons (61, 63) atteignent leurs positions extrêmes dans les cylindres d'alimentation (60) ou dans le cylindre d'actionnement (13, 14). La soupape d'inversion (21) peut être commandée hydrauliquement au moyen de soupapes de commutation (15 et 16) raccordées à un cylindre d'actionnement (14) et électriquement au moyen de commutateurs électriques (24, 25) sensibles à la position extrême postérieure du cylindre d'alimentation (61).
EP89903132A 1988-05-02 1989-03-15 Agencement de commande de pompes a double cylindre pour liquides epais Expired - Lifetime EP0402390B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3814824A DE3814824A1 (de) 1988-05-02 1988-05-02 Steuerungsanordnung fuer eine zweizylinder-dickstoffpumpe
DE3814824 1988-05-02

Publications (2)

Publication Number Publication Date
EP0402390A1 true EP0402390A1 (fr) 1990-12-19
EP0402390B1 EP0402390B1 (fr) 1992-06-03

Family

ID=6353371

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89903132A Expired - Lifetime EP0402390B1 (fr) 1988-05-02 1989-03-15 Agencement de commande de pompes a double cylindre pour liquides epais

Country Status (5)

Country Link
US (1) US5209649A (fr)
EP (1) EP0402390B1 (fr)
JP (1) JP2604046B2 (fr)
DE (2) DE3814824A1 (fr)
WO (1) WO1989011037A1 (fr)

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3910120A1 (de) * 1989-03-29 1990-10-04 Putzmeister Maschf Steuerungsanordnung fuer eine zweizylinder-dickstoffpumpe
DE4115606A1 (de) * 1991-05-14 1992-11-19 Putzmeister Maschf Ueberlast-schutzeinrichtung fuer einen als brennkraftmaschine ausgebildeten antriebsmotor einer hauptpumpe eines hydraulischen druckversorgungsaggregats
DE9217574U1 (de) * 1992-12-23 1993-05-27 Langerbein-Scharf GmbH & Co. KG, 4700 Hamm Steuerungsanordnung für eine Mehrzylinder-Dickstoffpumpe
DE4403213A1 (de) * 1994-02-03 1995-08-10 Putzmeister Maschf Einrichtung zur Antriebssteuerung einer Zweizylinder-Dickstoffpumpe
DE19652298A1 (de) * 1996-12-16 1998-06-18 Rexroth Mannesmann Gmbh Hochdruckpumpenanordnung
US6135719A (en) * 1997-12-29 2000-10-24 Oilquip, Inc. Method and apparatus for metering injection pump flow
US6135724A (en) * 1998-07-08 2000-10-24 Oilquip, Inc. Method and apparatus for metering multiple injection pump flow
DE19959217A1 (de) * 1999-12-08 2001-06-13 Putzmeister Ag Verfahren und Anordnung zum Betonieren von vertikalen Schächten
US6454542B1 (en) * 2000-11-28 2002-09-24 Laibe Corporation Hydraulic cylinder powered double acting duplex piston pump
DE102004015419A1 (de) * 2004-03-26 2005-10-13 Putzmeister Ag Vorrichtung und Verfahren zur Steuerung einer Dickstoffpumpe
DE102004015416A1 (de) * 2004-03-26 2005-10-13 Putzmeister Ag Vorrichtung und Verfahren zur Steuerung einer Dickstoffpumpe
DE102004025910B4 (de) * 2004-05-27 2009-05-20 Schwing Gmbh Antriebseinrichtung für eine Zweizylinderdickstoffpumpe und Verfahren zum Betrieb derselben
WO2013023454A1 (fr) * 2011-08-15 2013-02-21 湖南三一智能控制设备有限公司 Dispositif de pompage et machines d'ingénierie
DE102018109443B4 (de) 2018-04-19 2020-10-01 Sera Gmbh Kompressorvorrichtung und Kompressionsverfahren

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1104826B (de) * 1957-05-23 1961-04-13 Otto M Kaestner Pumpe zum Foerdern von Beton und aehnlichen dickfluessigen Massen
US3587236A (en) * 1969-11-17 1971-06-28 Royal Industries Pump
US3667869A (en) * 1970-03-04 1972-06-06 Karl Schlecht Dual cylinder-concrete pump
GB1452561A (en) * 1973-11-16 1976-10-13 Fogt Indmasch Apparatus for pumping wet concrete
US4105373A (en) * 1974-11-12 1978-08-08 Fogt Industriemaschinenvertretung A.G. Fluid distributor device for controlling an apparatus for pumping wet concrete and the like
IT1114648B (it) * 1977-08-18 1986-01-27 Italiana Forme Acciaio Valvola distributrice a tre vie per pompe a due cilindri per calcestruzzo
DE3243576A1 (de) * 1982-11-25 1984-05-30 Karl Dipl.-Ing. 7000 Stuttgart Schlecht Zweizylinder-kolbenpumpe, insbesondere fuer dickstoffe
DE3428629A1 (de) * 1984-08-03 1986-02-13 Klaus 6107 Reinheim Obermann Duplex-plunger-pumpe
GB8503501D0 (en) * 1985-02-12 1985-03-13 Thomsen Sales & Service Ltd A Reciprocatory pumps
DE3505541A1 (de) * 1985-02-18 1986-08-21 WIBAU AG, 6466 Gründau Verfahren zum antrieb einer pumpe fuer beton o.dgl. sowie eine pumpe zur ausuebung des verfahrens
DE3833845A1 (de) * 1988-10-05 1990-04-12 Putzmeister Maschf Dickstoffpumpe mit nachgeschaltetem absperrorgan
US5092744A (en) * 1990-03-14 1992-03-03 Possis Corporation Intensifier

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO8911037A1 *

Also Published As

Publication number Publication date
DE58901611D1 (de) 1992-07-09
EP0402390B1 (fr) 1992-06-03
DE3814824A1 (de) 1989-11-16
JPH03504404A (ja) 1991-09-26
US5209649A (en) 1993-05-11
WO1989011037A1 (fr) 1989-11-16
JP2604046B2 (ja) 1997-04-23

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