EP0437440A1 - Pompe a liquides epais avec organe d'arret en aval. - Google Patents

Pompe a liquides epais avec organe d'arret en aval.

Info

Publication number
EP0437440A1
EP0437440A1 EP89908698A EP89908698A EP0437440A1 EP 0437440 A1 EP0437440 A1 EP 0437440A1 EP 89908698 A EP89908698 A EP 89908698A EP 89908698 A EP89908698 A EP 89908698A EP 0437440 A1 EP0437440 A1 EP 0437440A1
Authority
EP
European Patent Office
Prior art keywords
valve
shut
pressure
cylinder
pump according
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
EP89908698A
Other languages
German (de)
English (en)
Other versions
EP0437440B1 (fr
Inventor
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 EP0437440A1 publication Critical patent/EP0437440A1/fr
Application granted granted Critical
Publication of EP0437440B1 publication Critical patent/EP0437440B1/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
    • F04B15/00—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts
    • F04B15/02—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts the fluids being viscous or non-homogeneous
    • F04B15/023—Pumps adapted to handle specific fluids, e.g. by selection of specific materials for pumps or pump parts the fluids being viscous or non-homogeneous supply of fluid to the pump by gravity through a hopper, e.g. without intake 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 thick matter pump with two alternating delivery cylinders opening into a material feed container via end openings with a feed line arranged inside the material feed container, alternately connectable on the inlet side to the openings of the conveying cylinders and releasing the other opening and outlet side with a feed line connectable pipe switch and with a shut-off device arranged behind the pipe switch in the conveying direction.
  • Pumps of this type are used to convey concrete and other pulpy masses, such as, for example, water spoil in tunnel structures or coal dust in water or heating oil in coal-firing systems.
  • the shut-off device in the pressure pipe enables working against high pressure without the risk of material backflow during the switching of the pipe switch.
  • the S-shaped swivel tube comes into consideration as the pipe switch. Basically, however, the use of U-shaped bent swivel tubes, pipe switches and downpipes is within the scope of the invention.
  • shut-off devices in the region of the conveying line, which can be designed, for example, as a seat valve, flat slide valve, flapper valve or rotary slide valve.
  • the invention is based on the object of taking precautions which ensure reliable chaining of the functional sequences even when the thick matter pump is operated with compressible media to be conveyed against excess pressure.
  • the inventive solution is based mainly on the Er ⁇ note that the shut-off device according to Renz pressure of an adjustable between 'of the delivery line and the pipe switch with hydrau ⁇ metallic or pneumatic means Diffe ⁇ from its closed position to its Offen ⁇ position must be reversible.
  • the shut-off device should be reversible from the closed position to the open position, especially when a predetermined precompression pressure in the pipe switch exceeds the pressure in the delivery line.
  • the shut-off device can be controlled by hydraulically or pneumatically actuated drive means via a preferably hydraulic sequence control so that the drive means when the pressure stroke is ended or reversed in the delivery cylinders and before the tube switch is reversed with unobstructed pressure medium and discharge in the closing direction of the shut-off element and after the subsequent switching of the pipe switch in the opening direction of the shut-off element can be actuated, an adjustable pressure-maintaining element being arranged in the pressure medium line for the pressure medium flowing off in the opening direction.
  • the pressure maintaining member is expediently bridged by a check valve opening in the inflow direction.
  • the pressure-maintaining member can be designed, for example, as a pressure-limiting valve or as a pressure-maintaining valve.
  • a further improvement in this regard can be achieved in that an adjustable pressure holding element is also arranged in the pressure medium line for the pressure medium flowing in the opening direction of the shut-off element.
  • one or two diverter switch cylinders and a reversing valve which is arranged in the hydraulic line to these cylinders and is provided via end position signals of the delivery cylinders or their drive cylinders, is located in the to an additional directional valve, which can be controlled in the forward direction by a signal which can be tapped in the blocking position of the shut-off element If the shut-off device has a hydraulic cylinder as the drive means, a hydraulic or electrical end position signal which controls the additional directional control valve can be tapped off in the locked position of the shut-off device on the hydraulic cylinder.
  • a hydraulically pilot-controllable reversing valve is arranged in the pressure medium lines leading to the drive means of the shut-off member, which can be controlled together with the diverter valve reversing valve via a common hydraulic pilot control line, with another pilot valve leading to the reversing valve reversing valve which can be actuated by end position signals is arranged in the diverter switch reversing cylinder.
  • a directional control valve which can be controlled by the end position signals of the delivery cylinder or its drive cylinder, is arranged in the pilot lines leading to the diverter valve reversing valve and to the shut-off valve reversing valve.
  • the shut-off element is designed as a seat valve, the valve seat of which is connected to the pressurized delivery line. line and its valve plate is arranged on the piston rod of a double-acting hydraulic cylinder forming the drive means.
  • the precompression can be achieved particularly simply by arranging in the pressure medium line leading to the bottom side connection of the hydraulic cylinder the nonreturn valve opening to the hydraulic cylinder and the adjustable pressure-maintaining element connected in parallel and connected on the input side to the hydraulic cylinder .
  • the drive cylinders actuating the delivery cylinders, the diverter switch cylinders and the drive cylinder for the shut-off device can be pressurized by a common variable displacement pump, the delivery volume of the variable displacement pump being able to be varied in accordance with the operating states which can be set via the sequence control.
  • the sequence control can also be implemented in a two-circuit arrangement, in which the drive cylinders for the feed cylinders, on the one hand, and the diverter valve reversing cylinders and drive means for the shut-off device, are actuated with various variable pumps.
  • the sequence control according to the invention can also be implemented in a free-flow arrangement using reversing pumps.
  • the single figure shows a circuit diagram of a sequence control for a two-cylinder thick matter pump with a subsequent switch. Abs * oerror ⁇ an in two reis hydraulic hydraulics.
  • the two-cylinder thick matter pump essentially consists of two delivery cylinders 1, 2, the front openings of which open into a material feed container 3 and can alternately be connected to a delivery line 5 via a pipe switch 4.
  • the delivery cylinders 1, 2 are driven in push-pull mode by means of hydraulic drive cylinders 6, 7, which in turn are pressurized with oil at the bottom via an adjustable hydraulic pump 102 and a reversing valve 40 and are hydraulically connected to one another at their rod-side end via a cross line 8.
  • a pressure compensation line 9 which contains a check valve and bridges the drive piston in question, is arranged at the two ends of the drive cylinder 7.
  • the variable displacement pump 102 draws pressure ⁇ l from a tank 104 via a suction filter 103.
  • the high pressure is protected by the safety valve 70.
  • the pressure oil reaches the main slide 40 via a non-return valve 41, which controls the high pressure on the cylinders 6 and 7 depending on the pilot control.
  • a shut-off device 83 which is designed as a seat valve in the exemplary embodiment shown and which, in the closed state, blocks the passage into the subsequent delivery area 84.
  • the shut-off device 83 is driven by a hydraulic cylinder 82.
  • the valve plate 83 is arranged at the front end of the projecting part of the piston rod of the hydraulic cylinder 82.
  • the hydraulic cylinder 82 and the reversing cylinders 71, 72 of the pipe switch are supplied with pressure oil via an auxiliary pump 106.
  • auxiliary pump 106 there are also circling arrangements with only one main oil pump as well the use of reversing pumps for the pressure medium loading of the individual consumers is possible without changing the sequence of the control arrangement.
  • the piston of the drive cylinder 6 reaches the switching valve 13 on the rod side and triggers a hydraulic pulse there, which is switched to the pilot control of the electro-hydraulically locking directional control valve 10 via the directional control valve 50 which is in the spring-centered rest position .
  • the high pressure of the pump 106 reaches the valves 10 and 61 via the connection points 14 and 14 1 , which are separated from one another by a check valve.
  • the end position signal of the switching valve 13 acts on the valve 10 in the position shown in the drawing.
  • high pressure is applied to the pilot control of the diverter switch reversing valve 30 and through the valve 90 and the control unit 81 for piloting the reversing valve 80.
  • both the valve 30 and the valve 80 are reversed.
  • pressure ⁇ l is released from the connection point 14 via the previously switched pipe switch reversing valve 30 to one of the two switch switch cylinders 71, 72.
  • the end positions of the pipe switch are tapped via lines 73 and 74 on the pipe switch reversing cylinders 71, 72. From there, the end position signals reach the pilot control of the valve 90, which thus reverses the pilot control of the valve 80, which in turn exerts a rod-side opening pressure on the hydraulic cylinder 82 from the connection point 14 '.
  • the end position signal is also given via lines 73 and 74 via the operating mode valve 20 to the pilot control of the main slide 40. This causes the supply pressure to be changed over to the drive cylinders 6,7. In the illustrated example, the cylinder 7 is now subjected to pressure on the bottom side, so that the delivery cylinder 2 executes a pressure stroke.
  • the pressurized delivery cylinder 2 presses its material via the pipe switch 4 against the shut-off device 83, which is still in the closed position.
  • an overpressure can prevail due to process-related influences.
  • the shut-off device must then also be opened against this pressure. This takes place on the one hand through the hydraulic force, which acts on the rod side on the piston of the drive cylinder 82 of the shut-off element and can be adjusted via the pressure limiting valve 42. This force is opposed by the oil condition on the bottom, which is biased by the adjustable pressure relief valve 91.
  • the pressure limits accordingly valves 42 and 91, the force balance acting on the shut-off element 83 can be varied and a desired pre-compression set. The precompression ensures that there is no backflow from the area 84 under overpressure when the shut-off element 83 is opened.
  • valve 66 In the end positions of the drive cylinder 6 and the pressure on the bottom of the drive cylinder 82, the valve 66 is controlled and the safety valve 70 is opened via a signal tap in the feed line to the cylinder 82. This allows the main oil flow from the pump 102 to flow unhindered to the tank. The valve 66 is relieved when the shutoff member 83 is opened.
  • a disadvantage of this arrangement is that the oil quantity of the main pump flows to the tank without use during the changeover time. Appropriate measures can also be taken to ensure that the main delivery pump 102 is pivoted back to zero delivery rate during the changeover time.
  • the end position signals on the drive cylinders 6, 7, on the switch gate cylinder 71, 72 and on the hydrocylin 82 can also be picked up electrically by suitable sensors or proximity switches e1, e2, e3, e4 and e5 and used to reverse the directional control valves 10 ( e1, e2) or 90 (e3, e4) and for controlling the main oil pump 102 (e5).
  • Valves 20 and 50 are expediently mechanically connected to one another.
  • the operating modes zero, advance and recall can be initiated manually on the valve 20.
  • valve 50 In the "reclaim" position, valve 50 is also activated. If, as indicated in the drawing, the operating mode valve 20 is actuated electrically, the valve 50 is also actuated electrically in the “return” position.
  • the control unit 81 is supplied with electrical voltage via the connections 86 during normal operation of the system. Control lines 87 and 89 as well as 87 'and 89' are connected under supply voltage.
  • the shut-off element 83 is closed by acting on the cylinder 82 from the bottom.
  • the control unit 81 must therefore connect the lines 88 and 89 intrinsically safely, without voltage, and thus, regardless of the current switching position of the valve 80, ensure that the cylinder 82 is pressurized with oil on the base side and the shut-off element 83 closes . At the same time, line 89 'is then switched to tank line 88'.
  • the pressure reservoir 111 which can be pressurized with pressure ⁇ l by the pump 106 via the check valve 110, ensures that the shut-off element 83 closes due to the oil supply in the pressure reservoir 111 in the event of an oil supply failure.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

La pompe à liquides épais comporte deux cylindres de transport (1, 2) travaillant en alternance et débouchant, par des ouvertures du côté cylindre, dans un récipient d'alimentation en matériaux, et un tuyau de raccord mobile (4) agencé à l'intérieur du récipient d'alimentation en matériaux, qui, du côté entrée, peut être raccordé alternativement à une des ouvertures des cylindres de transport, l'autre ouverture restant libre, et qui, du côté sortie, peut être raccordé avec chacune des conduites de transport; ladite pompe comporte en outre un organe d'arrêt (83), agencé en aval du tuyau mobile de raccord, dans le sens du transport. Grâce à un système de réglage séquentiel, les moyens d'entraînement qui commandent l'organe d'arrêt (83) sont actionnés dans le sens de fermeture de l'organe d'arrêt (83) à la fin de chaque course de compression des cylindres de transport, avant que la position du tuyau de raccord mobile (4) ne soit modifiée, le moyen de pression arrivant et partant sans entraves dans le sens fermeture du tuyau de raccord mobile (4), et lesdits moyens d'entraînement sont actionnés dans le sens ouverture de l'organe d'arrêt (83) dès que la position du tuyau de raccord mobile est ensuite modifiée. Un organe de maintien de la pression réglable est agencé à l'intérieur de la conduite de moyen de pression pour le moyen de pression qui s'écoule dans le sens ouverture.
EP89908698A 1988-10-05 1989-08-03 Pompe a liquides epais avec organe d'arret en aval Expired - Lifetime EP0437440B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3833845 1988-10-05
DE3833845A DE3833845A1 (de) 1988-10-05 1988-10-05 Dickstoffpumpe mit nachgeschaltetem absperrorgan

Publications (2)

Publication Number Publication Date
EP0437440A1 true EP0437440A1 (fr) 1991-07-24
EP0437440B1 EP0437440B1 (fr) 1993-01-20

Family

ID=6364417

Family Applications (1)

Application Number Title Priority Date Filing Date
EP89908698A Expired - Lifetime EP0437440B1 (fr) 1988-10-05 1989-08-03 Pompe a liquides epais avec organe d'arret en aval

Country Status (5)

Country Link
US (1) US5127806A (fr)
EP (1) EP0437440B1 (fr)
JP (1) JP2522569B2 (fr)
DE (2) DE3833845A1 (fr)
WO (1) WO1990004103A1 (fr)

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3814824A1 (de) * 1988-05-02 1989-11-16 Putzmeister Maschf Steuerungsanordnung fuer eine zweizylinder-dickstoffpumpe
DE4127277A1 (de) * 1991-08-17 1993-02-18 Putzmeister Maschf Hydraulische steuerungseinrichtung fuer eine dickstoffpumpe
US5332372A (en) * 1992-04-20 1994-07-26 Warren Rupp, Inc. Modular double-diaphragm pump
IT1282148B1 (it) * 1996-04-30 1998-03-12 Cifa Spa Impianto per la erogazione di calcestruzzo additivat0, a flusso costante
US6419127B1 (en) * 1999-09-18 2002-07-16 Steven Fershtut Apparatus for raising concrete members
DE102004015419A1 (de) * 2004-03-26 2005-10-13 Putzmeister Ag Vorrichtung und Verfahren zur Steuerung einer Dickstoffpumpe
DE102011000834A1 (de) * 2011-02-21 2012-08-23 Babcock Borsig Steinmüller Gmbh Trockneranordnung
DE102013006333A1 (de) * 2013-04-12 2014-10-16 Liebherr-Betonpumpen Gmbh Zweizylinder-Dickstoffpumpe
ES2704235T3 (es) 2013-10-29 2019-03-15 Thermtech Holdings As Sistema para suministrar y bombear material menos bombeable en una línea de conducto
CA3113428C (fr) 2018-09-28 2021-08-24 Julio Vasquez Systeme de surveillance de systemes de pompage de beton
DE102018130480A1 (de) * 2018-11-30 2020-06-04 Liebherr-Betonpumpen Gmbh Zweizylinder-Dickstoffpumpe

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2123583A (en) * 1936-04-10 1938-07-12 Chain Belt Co Auxiliary valve structure for concrete pumps
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
US3981622A (en) * 1974-11-20 1976-09-21 Kelsey-Hayes Company Hydraulic intensifier control system
US4030860A (en) * 1976-03-15 1977-06-21 Standlick Ronald E Variable proportional metering apparatus
JPS53142731A (en) * 1977-05-19 1978-12-12 Bosch Gmbh Robert Vehicle consisting of guide section and driving section
IT1114648B (it) * 1977-08-18 1986-01-27 Italiana Forme Acciaio Valvola distributrice a tre vie per pompe a due cilindri per calcestruzzo
JPS5587867A (en) * 1978-12-25 1980-07-03 Mitsubishi Heavy Ind Ltd Concrete pump
EP0080385A1 (fr) * 1981-11-25 1983-06-01 Hands-England Drilling Limited Systèmes de pompage

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9004103A1 *

Also Published As

Publication number Publication date
WO1990004103A1 (fr) 1990-04-19
EP0437440B1 (fr) 1993-01-20
DE58903364D1 (de) 1993-03-04
JP2522569B2 (ja) 1996-08-07
DE3833845A1 (de) 1990-04-12
JPH04500992A (ja) 1992-02-20
US5127806A (en) 1992-07-07

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