EP0778419A2 - Appareil de commande hydraulique avec un distributeur commandé par pression - Google Patents

Appareil de commande hydraulique avec un distributeur commandé par pression Download PDF

Info

Publication number
EP0778419A2
EP0778419A2 EP96118169A EP96118169A EP0778419A2 EP 0778419 A2 EP0778419 A2 EP 0778419A2 EP 96118169 A EP96118169 A EP 96118169A EP 96118169 A EP96118169 A EP 96118169A EP 0778419 A2 EP0778419 A2 EP 0778419A2
Authority
EP
European Patent Office
Prior art keywords
pressure
valve
pump
control
working
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
EP96118169A
Other languages
German (de)
English (en)
Other versions
EP0778419B1 (fr
EP0778419A3 (fr
Inventor
Reiner Püschel
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.)
Bosch Rexroth AG
Original Assignee
Mannesmann Rexroth AG
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 Mannesmann Rexroth AG filed Critical Mannesmann Rexroth AG
Publication of EP0778419A2 publication Critical patent/EP0778419A2/fr
Publication of EP0778419A3 publication Critical patent/EP0778419A3/fr
Application granted granted Critical
Publication of EP0778419B1 publication Critical patent/EP0778419B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors

Definitions

  • the invention relates to a hydraulic valve arrangement with a pressure-controlled directional valve with two working connections and a control connection for controlling the pressure medium flow.
  • Such a valve arrangement is from the book The hydraulic trainer, volume 4, technology of the 2-way cartridge valves ", Mannesmann Rexroth GmbH, RE 00 280 / 01.89, 1989, ISBN 3-8023-0291-5, pages 49 to 53.
  • 2-way cartridge valves standardized according to DIN 24 342, they have two work connections and a control connection and are designed for installation in control blocks.
  • the control of the 2-way installation valves is purely pressure-dependent. On a control piston, which depending on its position blocks the connection between the work connections or opens, the pressures at the working ports act on one side and the pressure at the control port and the force of a spring on the other side.
  • the space between the control piston and the control port is called the spring chamber.
  • the control piston of the 2-way cartridge valve blocks the flow of the pressure medium between the work connections in both directions.
  • the control connection is connected to the tank. Since the forces acting on the control piston from the working connections are now greater than the forces acting on the control piston from the control pressure side, the control piston is displaced in the direction of the control connection.
  • the control piston releases the connection between the working connections and displaces pressure medium from the spring chamber into the tank.
  • the movement between the control piston increases the space between the working connections and the control piston. The increased volume of this space must be filled up by the pump.
  • the outlet pressure of the pump drops briefly until this has happened. Even if this drop in pressure only lasts for a short time, this pressure fluctuation can lead to vibrations which have a disruptive effect, particularly in low-frequency systems.
  • the invention has for its object to provide a valve assembly of the type mentioned, in which switching operations do not lead to pressure fluctuations in the system.
  • the pressure medium that is displaced from the control chamber of the 2-way cartridge valve when the 2-way cartridge valve is opened is not discharged into the tank but remains in the system. This means that the pressure medium displaced from the control chamber is supplied to the consumer or the pump together with the pressure medium that has flowed through the 2-way cartridge valve in accordance with the direction of flow of the pressure medium. Since the amount of pressure medium in the system remains constant, there is no pressure drop when switching the 2-way cartridge valve. Both when opening and when closing, there is a smooth transition without delay.
  • the direction of flow of the pressure medium is determined by the working position of two pilot valves. In each flow direction, the valve arrangement acts like a check valve.
  • valve assembly closes if the system pressure fails.
  • a break in the line between the pump and the valve arrangement therefore does not lead to an unacceptable drop in the load due to the pressure medium failure.
  • the valve assembly is due to its function as a check valve in the open state for the control of safety-related hydraulic devices in which a single-acting cylinder is supplied with pressure medium by a pump, such as. B. hydraulic lifts, can be used advantageously. If the pressure medium supply fails during the lifting of the load, the valve arrangement closes automatically and prevents the load from dropping.
  • the piston speed of the single-acting cylinder can be adjusted by controlling the quantity of pressure medium delivered by the pump in the unit of time. A variable displacement pump or an inexpensive constant pump driven by a speed-controlled motor can be used for this.
  • FIG. 1 shows a schematic representation of a hydraulic device for controlling the pressure medium flow between a variable displacement pump 2 driven by an electric motor 1 and a single-acting cylinder 3, the piston 4 of which is loaded with the car 5 of an elevator.
  • the variable displacement pump 2 delivers pressure medium from a tank 6 via a line 7, a valve arrangement 8, a line 9, a filter device 10, a shut-off valve 11 and a pipe rupture protection device 12 to the cylinder 3.
  • the pump pressure (pressure in line 7) is p P denotes
  • the load pressure (pressure in line 9) is denoted by p L.
  • a pressure limiting valve 13 limits the pressure p P to a value which is greater than the greatest operational pressure in the line 7.
  • the downstream of the valve assembly 8 filter device 10 has a filter 16 and two check valves 17 and 18.
  • the check valves 17 and 18 are arranged so that the pressure medium can only flow in one direction over the filter 16, although the pressure medium in both directions over the Filter device 10 flows.
  • the direction of flow of the pressure medium flowing through the filter 16 is selected such that the pressure medium flowing back from the cylinder 3 to the tank 6 is filtered. This ensures that dirt particles such. B. at the sealing points between the piston 4 and the cylinder 5 in the pressure medium can be removed. Since only pressure medium that has previously passed through the filter 16 flows back to the tank 6, the pressure medium flowing from the tank 6 to the cylinder 3 no longer needs to be filtered separately.
  • the shut-off valve 11 and the pipe rupture protection device 12 are required in hydraulic elevators for safety reasons.
  • the shut-off valve 11 is constantly open during normal operation of the elevator. It is e.g. B. shut off during maintenance work on the elevator system.
  • the pipe rupture protection device 12 is also constantly open during normal operation of the elevator. Only when the quantity of pressure medium flowing out of the cylinder 3 in the unit of time is substantially greater than the largest quantity of pressure medium flowing out during operation, does the pipe rupture safety device interrupt the pressure medium flow and thus prevent the car from moving downward at an impermissibly high speed.
  • the pipe rupture protection device 12 is arranged as close as possible to the cylinder 3. Your specialist is familiar with the construction of such pipe burst safety devices. The pipe rupture protection device 12 is therefore not shown in detail in FIG. 1.
  • the valve arrangement 8 contains a pressure-controlled directional valve 19, two pilot valves 20 and 21, two check valves 22 and 23 and two throttles 24 and 25.
  • the directional valve 19 has two working ports A and B and a control port X.
  • the directional valve 19 has a control piston 26, which is subjected to forces from both sides.
  • the pressure present at the working port A acts on the base of the control piston 26.
  • the pressure present at the working connection B acts on the annular surface surrounding the base area from the same side. From the opposite side, the pressure at the control connection X acts on the control surface together with the force of a spring 27.
  • the control surface is equal to the sum of the Base area and the surrounding ring area.
  • the spool 26 blocks the connection between the working ports A and B if the forces acting on the control piston 26 from the control pressure side prevail, and opens the connection between the working ports A and B if the forces acting from the side of the working ports prevail.
  • the directional control valve 19 is a seat valve, ie the pressure medium flow is interrupted without leakage when the valve is closed.
  • the pilot valves 20 and 21 are electrically controlled switching valves designed as seat valves. In their rest position, they also block without leakage.
  • the pilot valve 20 bridges the throttle 24 and the check valve 22 in its working position.
  • the pilot valve 21 bridges the throttle 25 and the check valve 23 in its working position.
  • the magnets of the pilot valves 20 and 21 are connected to the switching outputs of the electrical control device 15 via lines 28 and 29, respectively.
  • the lines 28 and 29 are shown interrupted.
  • a first pressure transducer 30 converts the pressure p P into a proportional voltage u P.
  • a second pressure transducer 29 converts the pressure p L into a proportional voltage u L.
  • the voltages u P and u L are supplied to the electrical control device 15 as input signals.
  • An electrical switch 32 with three positions is connected via lines 33 and 34 to two switching inputs of the control device 15. In one switch position, the switch 32 connects the line 33 to a supply voltage U. This switch position is assigned to the lifting of the car 5. In the second switch position, the switch 32 connects the line 33 to the supply voltage U. This switch position is assigned to the lowering of the car 5. In the middle switch position, neither line 33 nor line 34 is connected to supply voltage U. The car 5 stops in this switch position.
  • valve arrangement 8 The function of the valve arrangement 8 is described below with reference to FIGS. 2 to 4. Only those for Pressurizing the control connection X effective components of the valve assembly 8 shown.
  • FIG. 2 shows the pressurization of the control piston 26 of the directional control valve 19 when the pilot valves 20 and 21 are in the rest position.
  • the pilot valves 20 and 21 are not effective in their rest position. They are therefore not shown in FIG. 2.
  • the pump pressure p P acts via the working connection A and the load pressure p L via the working connection B.
  • the pressure at the control connection X acts together with the spring 27.
  • the spring 27 is designed so that its force in relation to the control surface of the control piston 26 is of the order of one twentieth of that due to the weight and load of the car 5 and corresponds to certain load pressure p L due to the design of the cylinder 3.
  • the check valves 22 and 23 act like a shuttle valve.
  • the force exerted on the control piston 26 by the load pressure p L via the control connection X is already greater (without taking into account the influence of the spring 27) than the forces exerted by the pump pressure p P and the load pressure p L at the working ports A and B from the opposite side on the control piston 26, the directional control valve 19 is closed. If the pilot valves 20 and 21 are in the rest position, the directional control valve 19 is independent of whether the pump pressure p P is greater than that Load pressure p L or whether the load pressure p L is greater than the pump pressure p P - closed.
  • FIG. 3 shows the pressurization of the control piston 26 of the directional control valve 19 when the pilot valve 20 is in the working position and the pilot valve 21 in the rest position.
  • the pilot valve 20 bridges the check valve 22 and the throttle 24. Since the check valve 22 and the throttle 24 are not effective, they are not shown in FIG. 3.
  • the pilot valve 21 is not effective in its rest position. It is therefore also not shown in FIG. 3.
  • the pump pressure p P acts via the working connection A and the load pressure p L via the working connection B.
  • the pressure at the control port X acts together with the spring 27.
  • the pressure at the control port X is equal to the pressure at the working port B, that is to say your load pressure p L. If the pump pressure p P is less than the load pressure p L , the check valve 23 is closed. The force exerted by the load pressure p L via the control connection X on the control piston 26 (even without taking into account the influence of the spring 27) is greater than that of the pump pressure p P and your load pressure p L at the working connections A and B by the opposite Exerted forces on the control piston 26, the directional control valve 19 is closed. When the pump pressure p P increases to a value which is greater than the load pressure p L , the check valve 23 opens.
  • Pressure line flows from line 7 via throttle 25, check valve 23 and pilot valve 20 to line 9.
  • the amount of Pressure medium flowing through the throttle 25 is determined by the size of the throttle 25 and the difference between the pump pressure p P and the load pressure p L.
  • the load pressure P L is determined by the weight and load of the car 5 and by the design of the cylinder 3.
  • the directional control valve 19 is still closed, pressure medium is already flowing via the throttle 25 to the cylinder 3.
  • the pump pressure p P thus increases To the extent that the forces acting from the side of the working connections A and B on the control piston 26 outweigh the forces acting from the opposite side, the directional control valve 19 opens the connection between the working connection A and the working connection B.
  • the pressure medium delivered by the variable displacement pump 2 now flows via the line 7, the working connections A and B of the directional control valve 19 and the line 9 to the cylinder 3 and lifts the car 5.
  • the speed of the car 5 is determined by the amount of pressure medium flowing in the time unit. If the pressure in line 7 drops below the pressure in line 9, e.g. B. because of a break in the line 7 between the variable displacement pump 2 and the valve arrangement 8 or because the pump pressure p P has been reduced by the adjusting device 14 or because the adjusting pump 2 has been switched off, the forces acting on the control surface of the control piston 26 predominate and that Directional control valve 19 interrupts the flow of the pressure medium.
  • the valve arrangement 8 since the check valve 23 also closes when the pressure in the line 9 is greater than the pressure in the line 7, the valve arrangement 8, when the pilot valve 20 is actuated, behaves like a check valve which only has a flow of the pressure medium from the line 7 to the line 9 allowed.
  • FIG. 4 shows the pressurization of the control piston 26 of the directional control valve 19 when the pilot valve 21 is in the working position is located and the pilot valve 20 in the rest position.
  • the pilot valve 21 bridges the check valve 23 and the throttle 25 in its working position. Since the check valve 23 and the throttle 25 are not effective, they are not shown in FIG.
  • the pilot valve 20 is not effective in its rest position. It is therefore also not shown in FIG. 4.
  • the pump pressure p P acts via the working connection A and the load pressure p L via the working connection B.
  • the pressure at the control port X acts together with the spring 27.
  • the pressure at the control port X is equal to the pressure at the working port A, that is to say the pump pressure p P. If the pump pressure p P is greater than the load pressure p L , the check valve 22 is closed. The force exerted by the pump pressure p P via the control connection X on the control piston 26 (even without taking into account the influence of the spring 27) is greater than that of the pump pressure p P and the load pressure p L at the working connections A and B of the opposite one Exerted forces on the control piston 26, the directional control valve 19 is closed. If the pump pressure p P is now reduced to a value which is lower than the load pressure p L , the check valve 22 opens.
  • Pressure line flows from line 9 via throttle 24, check valve 22 and pilot valve 21 to line 7.
  • the amount of Pressure medium flowing via the throttle 24 is determined by the size of the throttle 24 and the difference between the load pressure p L and the pump pressure p P.
  • the load pressure p L is determined by the weight and load of the car 5 and by the design of the cylinder 3. If the pump pressure p P is further reduced, the forces acting from the side of the working connections A and B on the control piston 26 outweigh the forces acting from the opposite side, and the directional control valve 19 opens the connection between the working connection B and the working connection A.
  • the pressure medium displaced by the weight and load of the car 5 from the cylinder 3 flows through the filter 16, the line 9, the working connections B and A of the directional control valve 19, the line 7 and the variable pump 2 to the tank 6 and the car 5 sinks .
  • the variable displacement pump 2 acts as a hydraulic motor and drives the electric motor 1, which in turn acts as a generator and feeds electricity back into the network.
  • the speed of the car 5 is determined by the amount of pressure medium flowing in the time unit. If the pump pressure p P increases , e.g. B. due to a malfunction of the variable displacement pump 2 via the load pressure p L , the forces acting on the control surface of the control piston 26 predominate and the directional control valve 19 interrupts the flow of the pressure medium. Since the check valve 22 also closes when the pump pressure p P is greater than the load pressure p L , the valve arrangement 8, when the pilot valve 21 is activated, behaves like a check valve which only allows the pressure medium to flow from line 9 to line 7.
  • the valve arrangement 8 blocks in both directions when both pilot valves 20 and 21 are in the rest position. While the valve arrangement from the line 9 to line 7 blocks leakage, with the valve arrangement 8 closed, a leakage current can flow from the line 7 via the throttle 25 and the check valve 23 from the control connection X to the working connection B, the size of which depends, inter alia, on the design of the directional valve 19 depends.
  • the valve arrangement 8 behaves like a check valve, whose flow direction depends on which of the pilot valves 20 or 21 is in the working position.
  • the valve arrangement 8 has a gentle opening behavior both for the lifting process and for the lowering process, which prevents pressure oscillations from occurring due to the switching process of the directional control valve 19.
  • the shown in the Figure 1 electrical control device 15 controls the movement of the car 5.
  • the control means 15 are for this purpose by the transmitter 30, the pump pressure P P proportional voltage u P and the load pressure of the transducer 31 p L proportional voltage u L as input signals fed.
  • the switch 32 supplies the control device 15 with the supply voltage U via the lines 33 and 34, depending on whether the car 5 is to be raised or lowered.
  • the control device 15 controls the adjusting device 14 of the variable pump 2 and the magnets of the pilot valves 20 and 21 of the valve arrangement 8.
  • the middle position of the switch 32 is assigned to the holding process.
  • the solenoids of the pilot valves 20 and 21 are not activated. Since the valve assembly 8 locks as described above, no pump pressure is required to hold the car 5 in place.
  • the adjusting device 14 is therefore controlled by the control device 15 so that it adjusts the variable pump 2 so that the pump pressure p P has only a minimal value.
  • the control device 15 controls the magnet of the pilot valve 20.
  • the valve arrangement 8 behaves as described above when the pilot valve 20 is actuated, like a check valve which only allows a pressure medium flow from the adjusting pump 2 to the cylinder 3.
  • the adjusting device 14 is controlled by the control device 15 so that it adjusts the volume flow of the adjusting pump 2 in such a way that the pump pressure p P assumes a value which is at least larger than the load pressure p L by the amount required for opening the valve arrangement 8.
  • the pilot valve 20 is first activated and then the volume flow to the valve arrangement 8 is increased via the variable pump 2.
  • the car stops if the pressure supply fails due to a fault. A sinking of the car is effectively prevented by the function of the valve arrangement 8 as a check valve.
  • the control device 15 controls the magnet of the pilot valve 21.
  • the valve arrangement 8 behaves like a check valve which only allows a pressure medium flow from the cylinder 3 to the variable displacement pump 2.
  • the adjusting device 14 is controlled by the control device 15 so that the pump pressure p P is equal to the load pressure p L.
  • the pilot valve 21 is then actuated. Now the pump swivels to the minus and pumps oil into the tank 6 in accordance with the setpoint program of the control device 15. Since the direction of the volume flow reverses due to the load, the variable pump 2 works as a hydraulic motor and drives the electric motor 1. This now works as a generator and feeds electricity back into the electrical network.
  • a constant pump driven by a speed-controlled electric motor in particular a frequency-controlled electric motor
  • the control device for the speed of the electric motor is connected to the output of the control device 15. It is also possible to drive the constant pump at a constant speed and the Pump pressure p P to be controlled via a pressure relief valve with an adjustable relief pressure.
  • valve arrangement according to the invention is not limited to the control of hydraulic elevators. It is in the same way for the control of other safety-related hydraulic consumers, such as. B. the hoists of forklifts or tractors, suitable.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Forklifts And Lifting Vehicles (AREA)
EP96118169A 1995-12-07 1996-11-13 Appareil de commande hydraulique avec une soupape à deux voies pilotée par pression Expired - Lifetime EP0778419B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19545657 1995-12-07
DE19545657A DE19545657A1 (de) 1995-12-07 1995-12-07 Hydraulische Ventilanordnung mit einem druckgesteuerten Wegeventil

Publications (3)

Publication Number Publication Date
EP0778419A2 true EP0778419A2 (fr) 1997-06-11
EP0778419A3 EP0778419A3 (fr) 1998-06-03
EP0778419B1 EP0778419B1 (fr) 2001-01-24

Family

ID=7779444

Family Applications (1)

Application Number Title Priority Date Filing Date
EP96118169A Expired - Lifetime EP0778419B1 (fr) 1995-12-07 1996-11-13 Appareil de commande hydraulique avec une soupape à deux voies pilotée par pression

Country Status (2)

Country Link
EP (1) EP0778419B1 (fr)
DE (2) DE19545657A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1895168A1 (fr) * 2006-09-01 2008-03-05 Parker Hannifin Aktiebolag Arrangement de soupapes
CN113510176A (zh) * 2020-04-10 2021-10-19 初冠南 一种充压镦形成形装置

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE7512442U (fr) * Danfoss A/S, Nordborg (Daenemark)
JPS585502A (ja) * 1981-06-29 1983-01-12 Uchida Yuatsu Kiki Kogyo Kk 昇降シリンダの制御回路装置
US4401009A (en) * 1972-11-08 1983-08-30 Control Concepts, Inc. Closed center programmed valve system with load sense
EP0514782A1 (fr) * 1991-05-20 1992-11-25 GMV MARTINI S.p.A. Circuit hydraulique pour ascenseurs et monte charges où similaires

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1775178A1 (de) * 1968-07-13 1971-07-08 Rexroth Gmbh G L Vorgesteuertes Druckbegrenzungsventil
DE3521815A1 (de) * 1985-06-19 1987-01-02 Bosch Gmbh Robert Steuereinrichtung fuer hydraulische arbeitsmaschinen
DE4309901B4 (de) * 1992-11-10 2010-07-01 Zf Sachs Ag Hydraulischer Stellantrieb - inbesondere für eine Kraftfahrzeug-Reibungskupplung
DE4334607A1 (de) * 1993-10-11 1995-04-13 Rexroth Mannesmann Gmbh 2-Wege-Einbauventil mit Druckbegrenzungsfunktion
US5535588A (en) * 1994-05-06 1996-07-16 Dana Corporation Filter arrangement for single-acting telescopic hydraulic cylinders

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE7512442U (fr) * Danfoss A/S, Nordborg (Daenemark)
US4401009A (en) * 1972-11-08 1983-08-30 Control Concepts, Inc. Closed center programmed valve system with load sense
JPS585502A (ja) * 1981-06-29 1983-01-12 Uchida Yuatsu Kiki Kogyo Kk 昇降シリンダの制御回路装置
EP0514782A1 (fr) * 1991-05-20 1992-11-25 GMV MARTINI S.p.A. Circuit hydraulique pour ascenseurs et monte charges où similaires

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN vol. 007, no. 079 (M-204), 31.März 1983 & JP 58 005502 A (UCHIDA YUATSU KIKI KOGYO KK), 12.Januar 1983, *

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1895168A1 (fr) * 2006-09-01 2008-03-05 Parker Hannifin Aktiebolag Arrangement de soupapes
US8833391B2 (en) 2006-09-01 2014-09-16 Parker-Hannifin Corporation Valve arrangement
CN113510176A (zh) * 2020-04-10 2021-10-19 初冠南 一种充压镦形成形装置
CN113510176B (zh) * 2020-04-10 2024-01-19 初冠南 一种充压镦形成形装置

Also Published As

Publication number Publication date
DE19545657A1 (de) 1997-06-12
EP0778419B1 (fr) 2001-01-24
DE59606377D1 (de) 2001-03-01
EP0778419A3 (fr) 1998-06-03

Similar Documents

Publication Publication Date Title
EP1450048B1 (fr) Agencement de vanne
EP0473030A1 (fr) Distributeur proportionnel à siège à 4 voies
DE4100988C2 (de) Hydraulisches Antriebssystem
EP1574474A2 (fr) Agencement hydraulique
DE2651325A1 (de) Lastgesteuertes stroemungsmittelsystem
EP0275968A2 (fr) Dispositif de commande pour une transmission hydrostatique pour au moins deux utilisateurs
DE2748079C2 (de) Wasserdruck-Verstärkungsanlage
DE4235709A1 (de) Hydrostatisches Antriebssystem
DE4235707B4 (de) Hydrostatisches Antriebssystem
DE19831595B4 (de) Hydraulische Schaltung
DE4108915C2 (de) Hydraulische Einrichtung zur Druckmittelversorgung eines bevorrechtigten Primärlastkreises
WO1998021484A1 (fr) Systeme de soupape et procede de realisation
DE10219717B3 (de) Hydraulische Ventilanordnung
DE3420674C2 (de) Druckversorgungseinrichtung für ein Hydrauliksystem
DE3844400C2 (de) Ventilanordnung für ein hydraulisches System
EP0778419B1 (fr) Appareil de commande hydraulique avec une soupape à deux voies pilotée par pression
EP0884486B1 (fr) Dispositif de serrage électrohydraulique
DE9210647U1 (de) Hydraulische Steuervorrichtung
EP3135924B1 (fr) Commande hydraulique
DE3844405C2 (de) Ventilanordnung für ein hydraulisches System
EP1954949B1 (fr) Dispositif hydraulique de commande
WO2005093263A1 (fr) Systeme de commande hydraulique
DE3844399C2 (de) Steueranordnung für mehrere unabhängig voneinander betätigbare hydraulische Verbraucher und deren Verwendung
EP3464908A1 (fr) Système de vannes
EP0746690B1 (fr) Systeme regulateur pour pompe hydraulique

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE FR GB IT

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): DE FR GB IT

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: MANNESMANN REXROTH AG

17P Request for examination filed

Effective date: 19980918

RTI1 Title (correction)

Free format text: HYDRAULIC VALVE CONTROL WITH PRESSURE PILOTED TWO WAYS VALVE

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAG Despatch of communication of intention to grant

Free format text: ORIGINAL CODE: EPIDOS AGRA

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

RTI1 Title (correction)

Free format text: HYDRAULIC VALVE CONTROL WITH PRESSURE PILOTED TWO WAYS VALVE

17Q First examination report despatched

Effective date: 20000607

GRAH Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOS IGRA

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT

REF Corresponds to:

Ref document number: 59606377

Country of ref document: DE

Date of ref document: 20010301

ITF It: translation for a ep patent filed

Owner name: DE DOMINICIS & MAYER S.R.L.

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 20010430

Year of fee payment: 6

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 20010425

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 20021106

Year of fee payment: 7

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20030731

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20031113

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 20031113

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES;WARNING: LAPSES OF ITALIAN PATENTS WITH EFFECTIVE DATE BEFORE 2007 MAY HAVE OCCURRED AT ANY TIME BEFORE 2007. THE CORRECT EFFECTIVE DATE MAY BE DIFFERENT FROM THE ONE RECORDED.

Effective date: 20051113

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20110125

Year of fee payment: 15

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 59606377

Country of ref document: DE

Effective date: 20120601

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20120601