EP1432878A1 - Control device - Google Patents

Control device

Info

Publication number
EP1432878A1
EP1432878A1 EP02735426A EP02735426A EP1432878A1 EP 1432878 A1 EP1432878 A1 EP 1432878A1 EP 02735426 A EP02735426 A EP 02735426A EP 02735426 A EP02735426 A EP 02735426A EP 1432878 A1 EP1432878 A1 EP 1432878A1
Authority
EP
European Patent Office
Prior art keywords
valve
accumulator
shut
working cylinder
control device
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
EP02735426A
Other languages
German (de)
French (fr)
Other versions
EP1432878B1 (en
Inventor
Michael Kühn
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.)
Hydac Technology GmbH
Original Assignee
Hydac Technology 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 Hydac Technology GmbH filed Critical Hydac Technology GmbH
Publication of EP1432878A1 publication Critical patent/EP1432878A1/en
Application granted granted Critical
Publication of EP1432878B1 publication Critical patent/EP1432878B1/en
Anticipated expiration legal-status Critical
Expired - Fee Related legal-status Critical Current

Links

Classifications

    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2203—Arrangements for controlling the attitude of actuators, e.g. speed, floating function
    • E02F9/2207—Arrangements for controlling the attitude of actuators, e.g. speed, floating function for reducing or compensating oscillations
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/2217—Hydraulic or pneumatic drives with energy recovery arrangements, e.g. using accumulators, flywheels
    • E—FIXED CONSTRUCTIONS
    • E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
    • E02F—DREDGING; SOIL-SHIFTING
    • E02F9/00—Component parts of dredgers or soil-shifting machines, not restricted to one of the kinds covered by groups E02F3/00 - E02F7/00
    • E02F9/20—Drives; Control devices
    • E02F9/22—Hydraulic or pneumatic drives
    • E02F9/226—Safety arrangements, e.g. hydraulic driven fans, preventing cavitation, leakage, overheating

Definitions

  • the invention relates to a control device, in particular for working machines, such as wheel loaders, excavators or the like, with at least one working tool, in particular a loading shovel, which can be actuated via at least one hydraulic working cylinder, with a control block for controlling the pressure medium paths between the working cylinder, a pressure medium supply and a tank at least one hydraulic accumulator and with a shut-off valve arranged between the working cylinder and the accumulator, which has a controllable valve member which is switched into its open position by means of the working cylinder for switching on the accumulator for the purpose of springing a load.
  • working machines such as wheel loaders, excavators or the like
  • at least one working tool in particular a loading shovel
  • a control block for controlling the pressure medium paths between the working cylinder, a pressure medium supply and a tank at least one hydraulic accumulator and with a shut-off valve arranged between the working cylinder and the accumulator, which has a controllable valve member which is switched into its open position
  • the hydraulic accumulator can also be connected to the pressure medium source via the fill line, the shut-off valve acting between the working cylinder and the accumulator being arranged directly in the fill line itself and the valve member of the shut-off valve in the closing direction from Storage pressure is applied and pressure is released in the opening direction.
  • the respective hydraulic accumulator is charged when the load is lifted by means of the respective working cylinder. If the storage pressure rises to a value corresponding to the load pressure, a separate seat valve closes for this purpose, the control chamber being acted upon by the storage pressure.
  • a 3-way valve is electrically reversed, which can also be done automatically, in which case the accumulator pressure corresponds to the load pressure on the piston side of the respective working cylinder, since the hydraulic damping accumulator previously corresponds to this pressure was charged via the Fultechnisch.
  • the suspension therefore takes place with the pressure prevailing in the piston chamber of the respective working cylinder, not with a higher or lower pressure which would otherwise result in an unwanted movement of the piston of the working cylinder.
  • a sagging of the load when switching on the respective hydraulic damping accumulator is avoided.
  • dynamic loads occur on the hydraulic working cylinder, for example in the form of pressure peaks, which can arise, among other things, from the fact that the working machine in the form of a wheel loader for loading the loading shovel moves into material to be picked up, such as gravel, soil or the like , these pressure peaks damaging the damping accumulator are passed on directly to the latter.
  • the invention has for its object to further improve the known solutions to the effect that a control device is created which offers increased safety in the field of work machines, such as wheel loaders, excavators or the like, and one Avoid overloading the memory due to occurring pressure peaks, especially when the machine is loading.
  • a relevant object is achieved by a control device with the features of the patent claim! In its entirety.
  • the damping accumulator is separated from the working cylinder and pressure peaks, for example when working with the working tool, such as Booms, loading shovels or the like, do not have a detrimental effect on the hydraulic accumulator.
  • the shut-off valve is then switched to its open position, with the switching valve in the Ful effet being shut off at the same time, and since the load to be cushioned is adapted to the earlier lifting and filling pressure of the accumulator, an extension movement of the working cylinder can occur.
  • control device according to the invention is explained in more detail using an embodiment according to the drawing.
  • the single figure shows a basic and not to scale representation in the manner of a circuit diagram of the essential main components of the control device according to the invention.
  • the control device is intended in particular for use in working machines, such as wheel loaders, excavators or the like.
  • At least one hydraulic working cylinder 10 which is provided with a piston rod unit 14 for lifting and lowering a predeterminable load 12, is used to actuate and control a loading or excavator shovel.
  • the actual piston of this unit 14 divides the working cylinder 10 into a piston chamber 16 and a rod chamber 18.
  • a plurality of working cylinders 10 (not shown), in particular connected in parallel to one another, can be provided.
  • a conventional control block 20 provided for these tasks is used to control the working cylinder 10.
  • the mentioned control block 20 is used to control the pressure medium paths between the working cylinder 10, a pressure medium supply P and a tank T.
  • control device has a hydraulic accumulator 22, which serves as a damping memory, whereby several memories can also be used depending on the task.
  • the accumulator 22 is of such a conventional type, which is also known as a “hydraulic accumulator”. Between the working cylinder 10 and the accumulator 22 there is a drain line 24, to which the control block 20 with its pressure supply P is connected in the Ful effet 24 a first switching valve 26 switched and a check valve 28 which opens spring-loaded in the direction of the memory 22.
  • the first switching valve 26 is in its position which blocks the flow line 24. Furthermore, an auxiliary branch line 30 is connected to the Ful effet 24, which is provided with a shut-off valve 32.
  • the shut-off valve 32 has a controllable valve member 34 which serves to switch on the accumulator 22 for damping the movement (suspension) of the working cylinder 10 and which can be switched into its open position for this purpose. As shown in the circuit diagram, the shut-off valve 32, in its starting position, assumes its position which blocks the secondary branch line 30.
  • the switching valve 26 and the shut-off valve 32 are therefore connected in parallel to one another to the ful line 24 or the secondary branch line 30, ie the secondary branch line 30 opens with its two free ends in the respective fluid direction before and after the switching valve 26 into the ful line 24 the connection points 36.38.
  • a further switching valve 40 is connected between the accumulator 22 and the shut-off valve 32 in the secondary branch line 30, which is shown in the non-actuated state and brings the valve member 34 of the shut-off valve 32 into its open position in the actuated state. In the non-actuated state, the further switching valve 40 is connected to a leak oil line L. Said second switching valve 40 can be activated and actuated in particular by the operator of the working machine.
  • the storage pressure is passed to the shut-off valve 32 via the part of the secondary branch line 30 which is connected to the accumulator 22 and this is switched into its open position.
  • the further switching valve 40 is connected to the secondary branch line 30 via the connection point 42, specifically between the connection point 38 and the shut-off valve 32.
  • the rod chamber 18 of the working cylinder 10 is connected to the control block 20 via a connecting line 43 and to a third switching valve 46 via a further connecting line 44. Furthermore, the third switching valve 46 is connected to the tank T and, as the circuit diagram shows , also control via a control line 48 and therefore via the second switching valve 40. By actuating the third switching valve 46, this is brought from the locked position into its open position via the control line 48 and the rod chamber 18 can relax towards the tank T. Furthermore, a pressure relief valve 50 is connected to the leak oil line L, which is otherwise connected to the connection point 38 with the accumulator 22. A shut-off device 52 which can be operated by hand is also provided running parallel to the pressure relief valve.
  • Said valve arrangement can be combined in a valve block 54, the working cylinder 10 with connections A, B being connectable to this valve block 54.
  • the memory 22 can be connected to the valve block 54 via the connection Sp, and a control line of the control block 20 opens into the valve block 54 via the connection VStö for controlling the first switching valve 26.
  • Connections T and L are also used for connecting the tank or Leakage oil line provided.
  • the first switching valve 26 as well as the third switching valve 46 and the shut-off valve 32 are designed as 2/2-way valves and are all blocked in their basic position.
  • the second switching valve 40 consists of a 3/2-way valve which, in the non-actuated state, establishes a fluid-carrying connection between the control line 48 and the leakage oil line L.
  • Both the shut-off valve 32 and the third switching valve 56 must master large volume flows, the volume flow that passes through the third switching valve 46 being smaller than that which passes through the shut-off valve 32. This is due to the fact that the third switching valve 46 is assigned to the rod chamber 18 and the shut-off valve 32 to the piston chamber 16, which lead to different volume flows when the volume changes. When the working cylinder 10 is retracted, only a very small pressure difference is available in the third switching valve 46, which can be less than 1 bar.
  • the suspension itself remains blocked for filling the loading shovel and when unloading it, or if a boom is to be raised or lowered.
  • the control block 20 is actuated and the control oil or the flow of the pilot valve (VStö) opens that first switching valve 26, so that there is a fluid-carrying connection via the opening check valve 28.
  • the accumulator 22 is loaded via the check valve 28 with the maximum pressure occurring in the respective work cycle, so that the lifting pressure for the load 12 corresponds to the filling pressure of the accumulator 22.
  • the suspension can now be activated for driving with the working machine, the control block 20 being switched to its neutral position (closed). Now the second switching valve 40 is actuated, the two valves 32 and 46, which are pilot-controlled via the control line 48, being acted upon by the accumulator pressure and thereby opening.
  • the third switching valve 46 is switched and connects the rod chamber 18 to the tank T and the further switched shut-off valve 32 connects the piston chamber 16 of the working cylinder 10 to the accumulator 22, so that the suspension described is activated in this way.
  • the second switching valve 40 is actuated again, so that the pilot lines 48 of the valves 32 and 46 are connected to the tank line.
  • the named valves 32 and 46 therefore close, the accumulator 22 remaining charged and the suspension blocked.
  • the loading shovel can now move into the load, for example in the form of ballast, the high pressures which may arise in the lifting cylinders 10 not being passed on to the accumulator 22 in a damaging manner, since the first switching valve 26, which is designed as a slide valve, is located in the latter Moment remains closed and thus interrupts the fluid-carrying connection via the Ful effet 24.
  • the suspension itself only makes sense when driving, it is essentially only activated for driving and the control device according to the invention ensures that the suspension that the suspension is blocked when the storage 22 could be overloaded by pressure peaks when the load is introduced or when the work tool (loading shovel) which can be actuated by means of the working cylinder 10 assumes a working state with or without load, in which an undesired occurrence possibly caused by the storage 22 being switched on Movement process (lifting a boom or the like.) could be dangerous.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mining & Mineral Resources (AREA)
  • Civil Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Operation Control Of Excavators (AREA)

Abstract

The invention relates to a control device, in particular for working machines, such as wheel loaders, excavators or similar comprising at least one working tool (12) that can be actuated by means of at least one hydraulic working cylinder (10), in particular a loading shovel. Said device comprises a control block for controlling the hydraulic fluid paths between the working cylinder (10), a hydraulic fluid supply (P) and a tank (T). Said device also comprises at least one hydraulic accumulator (22) and a shut-off valve (32), which has a controllable valve member (34) and is located between the working cylinder (10) and the accumulator (22). Said valve member is connected in the transmission position for connecting the accumulator (22) in order to damp the motion of the working cylinder (10). A selector valve (26) that can be controlled by the control block (20) is connected in the fill line (24), blocking said line (24) in the non-actuated state and the shut-off valve (32) is connected in a secondary line (30) that is connected to the fill line (24), said shut-off valve being impinged in the open direction by accumulator pressure and being decompressed in the closed direction. This permits increased safety to be achieved for working machines and prevents an excess load from being placed on the damping accumulator.

Description

Steuervorrichtung control device
Die Erfindung betrifft eine Steuervorrichtung, insbesondere für Arbeitsmaschinen, wie Radlader, Bagger od. dgl., mit mindestens einem über mindestens einen hydraulischen Arbeitszylinder betätigbaren Arbeitswerkzeug, insbesondere Ladeschaufel, mit einem Steuerblock zur Ansteuerung der Druckmittelwege zwischen Arbeitszylinder, einer Druckmittelversorgung und einem Tank, mit mindestens einem hydraulischen Speicher und mit einem zwischen dem Arbeitszylinder und dem Speicher angeordneten Absperrventil, das ein ansteuerbares Ventilglied aufweist, das zum Zuschalten des Speichers zwecks Federn einer Last mittels des Arbeitszylinders in seine Durchlaßstellung geschaltet ist.The invention relates to a control device, in particular for working machines, such as wheel loaders, excavators or the like, with at least one working tool, in particular a loading shovel, which can be actuated via at least one hydraulic working cylinder, with a control block for controlling the pressure medium paths between the working cylinder, a pressure medium supply and a tank at least one hydraulic accumulator and with a shut-off valve arranged between the working cylinder and the accumulator, which has a controllable valve member which is switched into its open position by means of the working cylinder for switching on the accumulator for the purpose of springing a load.
Bei einer gattungsgemäßen Steuervorrichtung nach der DE 41 29 509 C2 ist der hydraulische Speicher über die Fulleitung mit der Druckmittelquelle gleichfalls verbindbar, wobei das zwischen dem Arbeitszylinder und dem Speicher wirkende Absperrventil unmittelbar in der Fulleitung selbst angeordnet ist und wobei das Ventilglied des Absperrventils in Schließrichtung vom Speicherdruck beaufschlagt und in Öffnungsrichtung druckentlastet ist.In a generic control device according to DE 41 29 509 C2, the hydraulic accumulator can also be connected to the pressure medium source via the fill line, the shut-off valve acting between the working cylinder and the accumulator being arranged directly in the fill line itself and the valve member of the shut-off valve in the closing direction from Storage pressure is applied and pressure is released in the opening direction.
Bei der bekannten Lösung erfolgt das Aufladen des jeweils hydraulischen Speichers beim Heben der Last mittels des jeweiligen Arbeitszylinders. Steigt der Speicherdruck auf einen dem Lastdruck entsprechenden Wert an, so schließt hierfür ein eigenes Sitzventil, dessen Steuerraum vom Speicherdruck beaufschlagt ist. Zum Zuschalten des jeweiligen hydraulischen Federungsspeichers auf den jeweiligen Arbeitszylinder wird ein 3-Wege-Ventil elektrisch umgesteuert, was auch automatisch erfolgen kann, wobei dann der Speicherdruck gleich dem Lastdruck auf der Kolbenseite des jeweiligen Arbeitszylinders entspricht, da ja vorher der hydraulische Dämpfungsspeicher auf diesen Druck über die Fulleitung aufgeladen wurde. Die Federung erfolgt also mit dem im Kolbenraum des jeweiligen Arbeitszylinders herr- sehenden Druck, nicht mit einem höheren oder niedrigeren Druck, der ansonsten eine ungewollte Bewegung des Kolbens des Arbeitszylinders zur Folge hätte. Insbesondere ist ein Absacken der Last beim Zuschalten des jeweiligen hydraulischen Dämpfungsspeichers vermieden. Treten jedoch an dem hydraulischen Arbeitszylinder dynamische Belastungen auf, beispiels- weise in Form von Druckspitzen, die unter anderem dadurch entstehen können, daß die Arbeitsmaschine in Form eines Radladers zum Beladen der Ladeschaufel in aufzunehmendes Gut, wie Schotter, Erdreich od. dgl., einfährt, werden diese den Dämpfungsspeicher schädigenden Druckspitzen unmittelbar an diesen weitergegeben.In the known solution, the respective hydraulic accumulator is charged when the load is lifted by means of the respective working cylinder. If the storage pressure rises to a value corresponding to the load pressure, a separate seat valve closes for this purpose, the control chamber being acted upon by the storage pressure. To switch on the respective hydraulic spring accumulator to the respective working cylinder, a 3-way valve is electrically reversed, which can also be done automatically, in which case the accumulator pressure corresponds to the load pressure on the piston side of the respective working cylinder, since the hydraulic damping accumulator previously corresponds to this pressure was charged via the Fulleitung. The suspension therefore takes place with the pressure prevailing in the piston chamber of the respective working cylinder, not with a higher or lower pressure which would otherwise result in an unwanted movement of the piston of the working cylinder. In particular, a sagging of the load when switching on the respective hydraulic damping accumulator is avoided. However, dynamic loads occur on the hydraulic working cylinder, for example in the form of pressure peaks, which can arise, among other things, from the fact that the working machine in the form of a wheel loader for loading the loading shovel moves into material to be picked up, such as gravel, soil or the like , these pressure peaks damaging the damping accumulator are passed on directly to the latter.
Zwar ist, um dem zu begegnen, bei einer bekannten Hydraulikanlage für Baumaschinen, insbesondere Radlader, Schlepper od. dgl., nach der DE 39 09 205 C1 bereits vorgeschlagen worden, innerhalb einer zu den hydraulischen Arbeitszylindern führenden Hauptleitung eine Verbindungs- leitung abzuzweigen, die mit einem Absperrventil versehen ist, das dann von der Fulleitung überbrückt ist, die wiederum ein Druckminderventil aufweist. Durch die dahingehend bekannte Anordnung ist es dann zwar möglich, den jeweiligen hydraulischen Speicher beim Heben der Last mittels des jeweiligen Hydraulikzylinders zu laden, und zwar mit einem durch das Druckminderventil vorgebbaren höheren Druck; allein beim Zuschalten der Dämpfungsspeicher über das Absperrventil auf die Kolbenseite des jeweiligen Arbeitszylinders entspricht der Druck auf der Kolbenseite nicht zwingend dem höheren Dämpfungsdruck auf Seiten der Speicher, so daß es auch ungewollt zu einer Ausfahrbewegung an den Arbeitszylindern und mithin an der Ladeschaufel kommen kann.In order to counteract this, it has already been proposed in a known hydraulic system for construction machinery, in particular wheel loaders, tractors or the like, according to DE 39 09 205 C1, to branch off a connecting line within a main line leading to the hydraulic working cylinders is provided with a shut-off valve, which is then bridged by the Fulleitung, which in turn has a pressure reducing valve. Because of the arrangement known in this respect, it is then possible to load the respective hydraulic accumulator when the load is lifted by means of the respective hydraulic cylinder, specifically with one the pressure reducing valve specifiable higher pressure; only when switching on the damping accumulator via the shut-off valve on the piston side of the respective working cylinder does the pressure on the piston side not necessarily correspond to the higher damping pressure on the part of the accumulator, so that there can also be an unintentional extension movement on the working cylinders and therefore on the loading shovel.
Ausgehend von diesem Stand der Technik liegt der Erfindung die Aufgabe zugrunde, die bekannten Lösungen dahingehend weiter zu verbessern, daß eine Steuervorrichtung geschaffen ist, die eine auf dem Gebiet der Arbeitsmaschinen, wie Radlader, Bagger od. dgl., erhöhte Sicherheit bietet und die eine Überlastung der Speicher aufgrund von auftretenden Druckspitzen, insbesondere im Beladebetrieb der Arbeitsmaschine, vermeiden hilft. Eine dahingehende Aufgabe löst eine Steuervorrichtung mit den Merkmalen des Patentanspruches ! in seiner Gesamtheit.Based on this prior art, the invention has for its object to further improve the known solutions to the effect that a control device is created which offers increased safety in the field of work machines, such as wheel loaders, excavators or the like, and one Avoid overloading the memory due to occurring pressure peaks, especially when the machine is loading. A relevant object is achieved by a control device with the features of the patent claim! In its entirety.
Dadurch, daß gemäß dem kennzeichnenden Teil des Patentanspruches 1 ein vom Steuerblock ansteuerbares Schaltventil in die Fulleitung geschaltet ist, das im unbetätigten Zustand die Fulleitung sperrt, und daß in einer an die Fulleitung angeschlossenen Nebenzweigleitung das Absperrventil geschaltet ist, das in Öffnungsrichtung vom Speicherdruck beaufschlagt ist und in Fließrichtung druckentlastet ist, kann über die Fulleitung der jeweilige hydraulische Speicher beim Heben der Last mittels des jeweiligen Arbeitszylinders aufgeladen werden, so daß der Speicherdruck dann dem He- bedruck unter Last entspricht. Wird die Fulleitung über das vom Steuerblock ansteuerbare Schaltventil dann abgesperrt und verbleibt das in der Nebenzweigleitung angeschlossene Absperrventil gleichfalls in Sperrstellung, ist der Dämpfungsspeicher vom Arbeitszylinder getrennt und Druckspitzen, die beispielsweise beim Arbeiten mit dem Arbeitswerkzeug, wie Ausleger, Ladeschaufel od. dgl., entstehen, wirken sich nicht schädlich auf den hydraulischen Speicher aus. Für die Aktivierung der Federung wird dann das Absperrventil in seine Durchlaßstellung geschaltet, bei gleichzeitig abgesperrtem Schaltventil in der Fulleitung, und da die abzufedernde Last dem früheren Hebe- und Fülldruck des Speichers angepaßt ist, kann es zu einer Ausfahrbewegung des Arbeitszylinders nach oben kommen. Mit der erfindungsgemäßen Steuervorrichtung ist also nicht nur der jeweilige hydraulische Dämpfungsspeicher vor schädlichen Druckspitzen bewahrt, sondern auch die Sicherheit beim Betrieb der Arbeitsmaschine erhöht.Characterized in that, according to the characterizing part of claim 1, a control valve controllable by the control block is switched into the Fulleitung, which blocks the Fulleitung in the unactuated state, and that the shut-off valve is connected in a branch line connected to the Fulleitung, which is acted upon in the opening direction by the accumulator pressure and is relieved of pressure in the direction of flow, the respective hydraulic accumulator can be charged via the Fulleitung when lifting the load by means of the respective working cylinder, so that the accumulator pressure then corresponds to the lifting pressure under load. If the ful line is then shut off via the switching valve that can be controlled by the control block and the shut-off valve connected in the secondary branch line also remains in the blocking position, the damping accumulator is separated from the working cylinder and pressure peaks, for example when working with the working tool, such as Booms, loading shovels or the like, do not have a detrimental effect on the hydraulic accumulator. For the activation of the suspension, the shut-off valve is then switched to its open position, with the switching valve in the Fulleitung being shut off at the same time, and since the load to be cushioned is adapted to the earlier lifting and filling pressure of the accumulator, an extension movement of the working cylinder can occur. With the control device according to the invention, not only is the respective hydraulic damping accumulator protected from harmful pressure peaks, but also the safety during operation of the working machine is increased.
Weitere vorteilhafte Ausführungsformen sind Gegenstand der weiteren Unteransprüche.Further advantageous embodiments are the subject of the further subclaims.
Im folgenden wird die erfindungsgemäße Steuervorrichtung anhand einer Ausführungsform nach der Zeichnung näher erläutert.In the following, the control device according to the invention is explained in more detail using an embodiment according to the drawing.
Dabei zeigt die einzige Figur in prinzipieller und nicht maßstäblicher Darstellung in der Art eines Schaltplanes die wesentlichen Hauptkomponenten der erfindungsgemäßen Steuervorrichtung.The single figure shows a basic and not to scale representation in the manner of a circuit diagram of the essential main components of the control device according to the invention.
Die erfindungsgemäße Steuervorrichtung ist insbesondere für den Einsatz bei Arbeitsmaschinen, wie Radlader, Bagger od. dgl., vorgesehen. Zum Betätigen und Ansteuern einer Lade- oder Baggerschaufel dient mindestens ein hydraulischer Arbeitszylinder 10, der zum Heben und Senken einer vorgebbaren Last 12 mit einer Kolbenstangeneinheit 14 versehen ist. Der ei- gentliche Kolben dieser Einheit 14 unterteilt dabei den Arbeitszylinder 10 in einen Kolbenraum 16 und einen Stangenraum 18. In Abhängigkeit der Ausbildung der Arbeitsmaschine können mehrere, insbesondere parallel zueinander geschaltete Arbeitszylinder 10 (nicht dargestellt) vorgesehen sein. Zum Ansteuern des Arbeitszylinders 10 dient ein für diese Aufgaben vorgesehener üblicher Steuerblock 20. Der genannte Steuerblock 20 dient der Ansteuerung der Druckmittelwege zwischen dem Arbeitszylinder 10, einer Druckmittelversorgung P und einem Tank T. Des weiteren weist die Steuer- Vorrichtung einen hydraulischen Speicher 22 auf, der als Dämpfungsspeicher dient, wobei hier ebenfalls in Abhängigkeit von der Aufgabenstellung auch mehrere Speicher eingesetzt werden können. Bei dem Speicher 22 handelt es sich um einen solchen üblicher Bauart, die auch unter der Bezeichnung „Hydrospeicher" bekannt sind. Zwischen Arbeitszylinder 10 und Speicher 22 verläuft eine Fulleitung 24, an die der Steuerblock 20 mit seiner Druckversorgung P angeschlossen ist. Des weiteren ist in die Fulleitung 24 ein erstes Schaltventil 26 geschaltet sowie ein Rückschlagventil 28, das in Richtung des Speichers 22 federbelastet öffnet.The control device according to the invention is intended in particular for use in working machines, such as wheel loaders, excavators or the like. At least one hydraulic working cylinder 10, which is provided with a piston rod unit 14 for lifting and lowering a predeterminable load 12, is used to actuate and control a loading or excavator shovel. The actual piston of this unit 14 divides the working cylinder 10 into a piston chamber 16 and a rod chamber 18. Depending on the design of the working machine, a plurality of working cylinders 10 (not shown), in particular connected in parallel to one another, can be provided. A conventional control block 20 provided for these tasks is used to control the working cylinder 10. The mentioned control block 20 is used to control the pressure medium paths between the working cylinder 10, a pressure medium supply P and a tank T. Furthermore, the control device has a hydraulic accumulator 22, which serves as a damping memory, whereby several memories can also be used depending on the task. The accumulator 22 is of such a conventional type, which is also known as a “hydraulic accumulator”. Between the working cylinder 10 and the accumulator 22 there is a drain line 24, to which the control block 20 with its pressure supply P is connected in the Fulleitung 24 a first switching valve 26 switched and a check valve 28 which opens spring-loaded in the direction of the memory 22.
In der gezeigten Schaltdarstellung befindet sich das erste Schaltventil 26 in seiner, die Fulleitung 24 sperrenden Stellung. Des weiteren ist an die Fulleitung 24 eine Nebenzweigleitung 30 angeschlossen, die mit einem Absperrventil 32 versehen ist. Das Absperrventil 32 weist ein ansteuerbares Ventilglied 34 auf, das dem Zuschalten des Speichers 22 zwecks Dämpfen der Bewegung (Federung) des Arbeitszylinders 10 dient und das hierfür in seine Durchlaßstellung schaltbar ist. Gemäß der Darstellung nach dem Schaltplan nimmt das Absperrventil 32 in seiner Ausgangslage jedoch seine, die Nebenzweigleitung 30 sperrende Stellung ein.In the switching illustration shown, the first switching valve 26 is in its position which blocks the flow line 24. Furthermore, an auxiliary branch line 30 is connected to the Fulleitung 24, which is provided with a shut-off valve 32. The shut-off valve 32 has a controllable valve member 34 which serves to switch on the accumulator 22 for damping the movement (suspension) of the working cylinder 10 and which can be switched into its open position for this purpose. As shown in the circuit diagram, the shut-off valve 32, in its starting position, assumes its position which blocks the secondary branch line 30.
Das Schaltventil 26 und das Absperrventil 32 sind also parallel zueinander an die Fulleitung 24 bzw. die Nebenzweigleitung 30 angeschlossen, d.h. die Nebenzweigleitung 30 mündet mit ihren beiden freien Enden in der jeweiligen Fluidrichtung vor und hinter dem Schaltventil 26 in die Fulleitung 24, und zwar an den Anschlußstellen 36,38. Wie sich des weiteren aus dem Schaltplan ergibt, ist zwischen Speicher 22 und dem Absperrventil 32 in die Nebenzweigleitung 30 ein weiteres Schaltventil 40 angeschlossen, das im nicht betätigten Zustand dargestellt ist und im betätigten Zustand das Ventilglied 34 des Absperrventils 32 in seine Öffnungsstellung bringt. Im nicht betätigten Zustand ist das weitere Schaltventil 40 an eine Leckölleitung L angeschlossen. Das genannte zweite Schaltventil 40 läßt sich insbesondere von der Bedienperson der Arbeitsmaschine ansteuern und betätigen. Ist das Schaltventil 40 in seine Betätigungs- Stellung durchgeschaltet, wird über den Teil der Nebenzweigleitung 30, die an den Speicher 22 angeschlossen ist, der Speicherdruck an das Absperrventil 32 geleitet und dieses in seine Durchlaßstellung geschaltet. Das weitere Schaltventil 40 ist hierzu über die Anschlußstelle 42 in die Nebenzweigleitung 30 geschaltet, und zwar zwischen der Anschlußstelle 38 und dem Absperrventil 32.The switching valve 26 and the shut-off valve 32 are therefore connected in parallel to one another to the ful line 24 or the secondary branch line 30, ie the secondary branch line 30 opens with its two free ends in the respective fluid direction before and after the switching valve 26 into the ful line 24 the connection points 36.38. As can also be seen from the circuit diagram, a further switching valve 40 is connected between the accumulator 22 and the shut-off valve 32 in the secondary branch line 30, which is shown in the non-actuated state and brings the valve member 34 of the shut-off valve 32 into its open position in the actuated state. In the non-actuated state, the further switching valve 40 is connected to a leak oil line L. Said second switching valve 40 can be activated and actuated in particular by the operator of the working machine. If the switching valve 40 is switched through to its actuating position, the storage pressure is passed to the shut-off valve 32 via the part of the secondary branch line 30 which is connected to the accumulator 22 and this is switched into its open position. For this purpose, the further switching valve 40 is connected to the secondary branch line 30 via the connection point 42, specifically between the connection point 38 and the shut-off valve 32.
Der Stangenraum 18 des Arbeitszylinders 10 ist über eine Anschlußleitung 43 mit dem Steuerblock 20 verbunden und über eine weitere Anschlußleitung 44 mit einem dritten Schaltventil 46. Des weiteren ist das dritte Schalt- ventil 46 an den Tank T angeschlossen und läßt sich, wie der Schaltplan zeigt, gleichfalls über eine Steuerleitung 48 ansteuern und mithin über das zweite Schaltventil 40. Durch Betätigen des dritten Schaltventils 46 wird dieses über die Steuerleitung 48 von seiner gesperrten Stellung in seine Durchlaßstellung gebracht und der Stangenraum 18 kann sich zum Tank T hin entspannen. Des weiteren ist an die Leckölleitung L ein Druckbegrenzungsventil 50 angeschlossen, das ansonsten an die Anschlußstelle 38 mit dem Speicher 22 angeschlossen ist. Parallel zum Druckbegrenzungsventil verlaufend ist des weiteren eine von Hand betätigbare Absperreinrichtung 52 vorgesehen. Die genannte Ventilanordnung kann in einem Ventilblock 54 zusammengefaßt sein, wobei an diesen Ventilblock 54 der Arbeitszylinder 10 mit Anschlüssen A,B anschließbar ist. Der Speicher 22 ist über den Anschluß Sp an den Ventilblock 54 anschließbar und zum Ansteuern des ersten Schalt- ventils 26 mündet eine Steuerleitung des Steuerblocks 20 über den Anschluß VStö in den Ventilblock 54. Ferner sind Anschlüsse T und L für den Anschluß der Tank- bzw. Leckölleitung vorgesehen. Das erste Schaltventil 26 sowie das dritte Schaltventil 46 und das Absperrventil 32 sind als 2/2-Wege-Ventile ausgebildet und in ihrer Grundstellung allesamt sperrend geschaltet. Das zweite Schaltventil 40 besteht aus einem 3/2-Wege-Ventil, das im nicht betätigten Zustand eine fluidführende Verbindung zwischen der Steuerleitung 48 und der Leckölleitung L herstellt. Sowohl das Absperrventil 32 als auch das dritte Schaltventil 56 müssen große Volumenströme beherrschen, wobei der Volumenstrom, der durch das dritte Schaltventil 46 geht, kleiner ist als derjenige, der das Absperrventil 32 passiert. Dies hängt damit zusammen, daß das dritte Schaltventil 46 dem Stangenraum 18 zugeordnet ist und das Absperrventil 32 dem Kolbenraum 16, die bei ihrer Volumenänderung zu unterschiedlichen Volumenströmen führen. Beim Einfahren des Arbeitszylinders 10 steht jedenfalls im dritten Schaltventil 46 nur eine sehr kleine Druckdifferenz zur Verfügung, die kleiner als 1 bar sein kann.The rod chamber 18 of the working cylinder 10 is connected to the control block 20 via a connecting line 43 and to a third switching valve 46 via a further connecting line 44. Furthermore, the third switching valve 46 is connected to the tank T and, as the circuit diagram shows , also control via a control line 48 and therefore via the second switching valve 40. By actuating the third switching valve 46, this is brought from the locked position into its open position via the control line 48 and the rod chamber 18 can relax towards the tank T. Furthermore, a pressure relief valve 50 is connected to the leak oil line L, which is otherwise connected to the connection point 38 with the accumulator 22. A shut-off device 52 which can be operated by hand is also provided running parallel to the pressure relief valve. Said valve arrangement can be combined in a valve block 54, the working cylinder 10 with connections A, B being connectable to this valve block 54. The memory 22 can be connected to the valve block 54 via the connection Sp, and a control line of the control block 20 opens into the valve block 54 via the connection VStö for controlling the first switching valve 26. Connections T and L are also used for connecting the tank or Leakage oil line provided. The first switching valve 26 as well as the third switching valve 46 and the shut-off valve 32 are designed as 2/2-way valves and are all blocked in their basic position. The second switching valve 40 consists of a 3/2-way valve which, in the non-actuated state, establishes a fluid-carrying connection between the control line 48 and the leakage oil line L. Both the shut-off valve 32 and the third switching valve 56 must master large volume flows, the volume flow that passes through the third switching valve 46 being smaller than that which passes through the shut-off valve 32. This is due to the fact that the third switching valve 46 is assigned to the rod chamber 18 and the shut-off valve 32 to the piston chamber 16, which lead to different volume flows when the volume changes. When the working cylinder 10 is retracted, only a very small pressure difference is available in the third switching valve 46, which can be less than 1 bar.
Zum besseren Verständnis der Funktionsweise der erfindungsgemäßen Steuervorrichtung wird diese im folgenden anhand einer Funktionsbe- Schreibung näher erläutert. Dabei ist vorgesehen, daß zum Befüllen der Ladeschaufel sowie bei ihrem Entladen oder, sofern ein Ausleger zu heben oder zu senken ist, die Federung an sich blockiert bleibt. Zum Bewegen der Last 12 über den hydraulischen Arbeitszylinder 10 wird der Steuerblock 20 betätigt und das Steueröl oder der Strom des Pilotventils (VStö) öffnet das erste Schaltventil 26, so daß dergestalt eine fluidführende Verbindung über das sich öffnende Rückschlagventil 28 gegeben ist. Beim Heben der Last 12 wird dabei der Speicher 22 über das genannte Rückschlagventil 28 mit dem maximal im jeweiligen Arbeitstakt auftretenden Druck geladen, so daß der Hebedruck für die Last 12 dem Fülldruck des Speichers 22 entspricht.For a better understanding of the mode of operation of the control device according to the invention, it is explained in more detail below on the basis of a functional description. It is provided that the suspension itself remains blocked for filling the loading shovel and when unloading it, or if a boom is to be raised or lowered. To move the load 12 over the hydraulic cylinder 10, the control block 20 is actuated and the control oil or the flow of the pilot valve (VStö) opens that first switching valve 26, so that there is a fluid-carrying connection via the opening check valve 28. When the load 12 is lifted, the accumulator 22 is loaded via the check valve 28 with the maximum pressure occurring in the respective work cycle, so that the lifting pressure for the load 12 corresponds to the filling pressure of the accumulator 22.
Zum Fahren mit der Arbeitsmaschine kann nun die Federung aktiviert werden, wobei der Steuerblock 20 auf seine Neutralstellung geschaltet (geschlossen) ist. Nun wird das zweite Schaltventil 40 betätigt, wobei die bei- den über die Steuerleitung 48 vorgesteuerten Ventile 32 und 46 mit dem Speicherdruck beaufschlagt werden und dabei öffnen. Das dritte Schaltventil 46 wird dabei geschaltet und verbindet den Stangenraum 18 mit dem Tank T und das weiter geschaltete Absperrventil 32 verbindet den Kolbenraum 16 des Arbeitszylinders 10 mit dem Speicher 22, so daß dergestalt die beschriebene Federung aktiviert ist.The suspension can now be activated for driving with the working machine, the control block 20 being switched to its neutral position (closed). Now the second switching valve 40 is actuated, the two valves 32 and 46, which are pilot-controlled via the control line 48, being acted upon by the accumulator pressure and thereby opening. The third switching valve 46 is switched and connects the rod chamber 18 to the tank T and the further switched shut-off valve 32 connects the piston chamber 16 of the working cylinder 10 to the accumulator 22, so that the suspension described is activated in this way.
Zur Deaktivierung der beschriebenen Federung wird wiederum das zweite Schaltventil 40 betätigt, so daß die Vorsteuerleitungen 48 der Ventile 32 und 46 mit der Tankleitung verbunden sind. Mithin schließen sich die ge- nannten Ventile 32 und 46, wobei der Speicher 22 geladen bleibt und die Federung blockiert ist. Bei blockierter Federung kann nun die Ladeschaufel in das Ladegut, beispielsweise in Form von Schotter, hineinfahren, wobei die in den Hubzylindern 10 möglicherweise entstehenden hohen Drücke nicht in schädigender Weise an den Speicher 22 weitergegeben werden, da das als Schieberventil ausgebildete erste Schaltventil 26 in diesem Moment geschlossen bleibt und somit die fluidführende Verbindung über die Fulleitung 24 unterbricht. Da die Federung an sich nur im Fahrbetrieb sinnvoll ist, wird sie im wesentlichen auch nur für den Fahrbetrieb aktiviert und über die erfindungsgemäße Steuervorrichtung ist sichergestellt, daß die Federung daß die Federung dann blockiert ist, wenn durch Druckspitzen bei der Lasteinleitung der Speicher 22 überlastet werden könnte oder wenn das mittels des Arbeitszylinders 10 betätigbare Arbeitswerkzeug (Ladeschaufel) mit oder ohne Last einen Arbeitszustand einnimmt, bei dem eine möglicherweise durch Zuschalten des Speichers 22 entstehender ungewollter Bewegungsvorgang (Anheben eines Auslegers od. dgl.) gefährlich werden könnte. To deactivate the suspension described, the second switching valve 40 is actuated again, so that the pilot lines 48 of the valves 32 and 46 are connected to the tank line. The named valves 32 and 46 therefore close, the accumulator 22 remaining charged and the suspension blocked. When the suspension is blocked, the loading shovel can now move into the load, for example in the form of ballast, the high pressures which may arise in the lifting cylinders 10 not being passed on to the accumulator 22 in a damaging manner, since the first switching valve 26, which is designed as a slide valve, is located in the latter Moment remains closed and thus interrupts the fluid-carrying connection via the Fulleitung 24. Since the suspension itself only makes sense when driving, it is essentially only activated for driving and the control device according to the invention ensures that the suspension that the suspension is blocked when the storage 22 could be overloaded by pressure peaks when the load is introduced or when the work tool (loading shovel) which can be actuated by means of the working cylinder 10 assumes a working state with or without load, in which an undesired occurrence possibly caused by the storage 22 being switched on Movement process (lifting a boom or the like.) Could be dangerous.

Claims

P a t e n t a n s p r ü c h e Patent claims
1. Steuervorrichtung, insbesondere für Arbeitsmaschinen, wie Radlader, Bagger od. dgl., mit mindestens einem, über mindestens einen hydrauli- sehen Arbeitszylinder (10) betätigbaren Arbeitswerkzeug (12), insbesondere Ladeschaufel, mit einem Steuerblock (20) zur Ansteuerung der Druckmittelwege zwischen dem Arbeitszylinder (10), einer Druckmittelversorgung (P) und einem Tank (T), mit mindestens einem hydraulischen Speicher (22) und mit einem zwischen dem Arbeitszylinder (10) und dem Speicher (22) angeordneten Absperrventil (32), das ein ansteuerbares Ventilglied (34) aufweist, das zum Zuschalten des Speichers (22) zwecks Dämpfen der Bewegung des Arbeitszylinders (10) in seine Durchlaßstellung geschaltet wird, dadurch gekennzeichnet, daß ein vom Steuerblock (20) ansteuerbares Schaltventil (26) in die Fulleitung (24) geschaltet ist, das im unbetätigten Zustand die Fulleitung (24) sperrt, und daß in einer an die Fulleitung (24) angeschlossenen Nebenzweigleitung (30) das Absperrventil (32) geschaltet ist, das in Öffnungsrichtung vom Speicherdruck beaufschlagt und in Schließrichtung druk- kentl astet ist.1. Control device, in particular for working machines, such as wheel loaders, excavators or the like, with at least one work tool (12), in particular a loading shovel, which can be actuated via at least one hydraulic working cylinder (10), with a control block (20) for controlling the pressure medium paths between the working cylinder (10), a pressure medium supply (P) and a tank (T), with at least one hydraulic accumulator (22) and with a shut-off valve (32) arranged between the working cylinder (10) and the accumulator (22) has a controllable valve member (34) which is switched to its open position for switching on the accumulator (22) in order to dampen the movement of the working cylinder (10), characterized in that a switching valve (26) which can be controlled by the control block (20) is connected to the fill line (24 ) is switched, which blocks the ful line (24) in the unactuated state, and that in a secondary branch line (30) connected to the ful line (24) the shut-off valve l (32) is switched, which is acted upon by the accumulator pressure in the opening direction and relieved of pressure in the closing direction.
2. Steuervorrichtung nach Anspruch 1 , dadurch gekennzeichnet, daß das Schaltventil (26) und das Absperrventil (32) parallel zueinander in Füll(24)- bzw. Nebenzweigleitung (30) angeschlossen sind und daß die Nebenzweigleitung (30) mit ihren beiden freien Enden in der jeweiligen Fluidrichtung vor und hinter dem Schaltventil (26) in die Fulleitung (24) münden.2. Control device according to claim 1, characterized in that the switching valve (26) and the shut-off valve (32) are connected in parallel to each other in filling (24) - or secondary branch line (30) and that the secondary branch line (30) with its two free ends open in the respective fluid direction upstream and downstream of the switching valve (26) into the ful line (24).
3. Steuervorrichtung nach Anspruch 1 oder 2, dadurch gekennzeichnet, daß in der Fulleitung (24) zwischen Schaltventil (26) und Speicher (22) ein in Richtung des Speichers (22) öffnendes Rückschlagventil (28) angeordnet ist.3. Control device according to claim 1 or 2, characterized in that in the Fulleitung (24) between the switching valve (26) and memory (22) a check valve (28) opening in the direction of the accumulator (22) is arranged.
4. Steuervorrichtung nach einem der Ansprüche 1 bis 3, dadurch gekenn- zeichnet, daß zwischen Speicher (22) und dem Absperrventil (32) an die4. Control device according to one of claims 1 to 3, characterized in that between the memory (22) and the shut-off valve (32) to the
Nebenzweigleitung (30) ein weiteres Schaltventil (40) angeschlossen ist, das im betätigten Zustand das Ventilglied (34) des Absperrventils (32) in seine Öffnungsstellung bringt.In addition to the branch line (30), a further switching valve (40) is connected, which in the actuated state brings the valve member (34) of the shut-off valve (32) into its open position.
5. Steuervorrichtung nach einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, daß der Kolbenraum (16) und der Stangenraum (18) des Arbeitszylinders (10) fluidführend an den Steuerblock (20) angeschlossen sind und der Kolbenraum (16) fluidführend mit der Fulleitung (24) in Verbindung steht.5. Control device according to one of claims 1 to 4, characterized in that the piston chamber (16) and the rod chamber (18) of the working cylinder (10) are fluid-carrying to the control block (20) and the piston chamber (16) fluid-carrying with the Fulleitung (24) communicates.
6. Steuervorrichtung nach Anspruch 5, dadurch gekennzeichnet, daß mittels eines dritten Schaltventils (46), das fluidführend an den Stangenraum (18) des Arbeitszylinders (10) angeschlossen ist, sich der Stangenraum (18) mit dem Tank (T) verbinden läßt.6. Control device according to claim 5, characterized in that by means of a third switching valve (46) which is fluidly connected to the rod chamber (18) of the working cylinder (10), the rod chamber (18) can be connected to the tank (T).
7. Steuervorrichtung nach Anspruch 6, dadurch gekennzeichnet, daß das dritte Schaltventil (46) ebenso wie das Absperrventil (32) gleichzeitig vom zweiten Schaltventil (40) angesteuert in seine Durchlaßstellung schaltbar ist.7. Control device according to claim 6, characterized in that the third switching valve (46) as well as the shut-off valve (32) is simultaneously controlled by the second switching valve (40) in its open position.
8. Steuervorrichtung nach einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, daß die an den Speicher (10) angeschlossene Fulleitung (24) über ein Druckbegrenzungsventil (50) abgesichert ist, das an eine Tankleitung (T) angeschlossen ist. 8. Control device according to one of claims 1 to 7, characterized in that the Fulleitung (24) connected to the memory (10) is secured by a pressure relief valve (50) which is connected to a tank line (T).
EP02735426A 2001-10-04 2002-06-27 Control device Expired - Fee Related EP1432878B1 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10148962A DE10148962C1 (en) 2001-10-04 2001-10-04 Hydraulic control device for digger or excavator has control block controlling switching valve in filling line and controlled valve in bypass line damping movement of hydraulic cylinders
DE10148962 2001-10-04
PCT/EP2002/007090 WO2003031734A1 (en) 2001-10-04 2002-06-27 Control device

Publications (2)

Publication Number Publication Date
EP1432878A1 true EP1432878A1 (en) 2004-06-30
EP1432878B1 EP1432878B1 (en) 2006-07-12

Family

ID=7701369

Family Applications (1)

Application Number Title Priority Date Filing Date
EP02735426A Expired - Fee Related EP1432878B1 (en) 2001-10-04 2002-06-27 Control device

Country Status (4)

Country Link
US (1) US7117670B2 (en)
EP (1) EP1432878B1 (en)
DE (2) DE10148962C1 (en)
WO (1) WO2003031734A1 (en)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN1867737B (en) * 2003-10-10 2010-04-28 株式会社小松制作所 Travel vibration suppressing device for working vehicle
DE102004010053A1 (en) * 2004-03-02 2005-09-29 Hydac System Gmbh suspension device
DE102014000696A1 (en) * 2014-01-14 2015-07-16 Hydac System Gmbh Device for locking and for pressure adjustment
JP6932635B2 (en) * 2017-12-28 2021-09-08 日立建機株式会社 Work vehicle

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3637709C3 (en) * 1986-11-05 1995-09-07 Ahlmann Baumaschinen Gmbh Self-propelled multi-purpose device
DE3909205C1 (en) * 1989-03-21 1990-05-23 Hanomag Ag, 3000 Hannover, De
US5195864A (en) * 1991-08-28 1993-03-23 Case Corporation Hydraulic system for a wheel loader
DE9208942U1 (en) * 1991-09-04 1993-01-14 O & K Orenstein & Koppel Ag, 1000 Berlin Hydraulic system for working machines equipped with working tools
US5513491A (en) * 1991-09-04 1996-05-07 O&K Orenstein & Koppel Ag Hydraulic vibration damping system for machines provided with tools
DE4129509C2 (en) * 1991-09-05 1994-06-16 Rexroth Mannesmann Gmbh Hydraulic control arrangement for construction machines
JP3115209B2 (en) 1995-04-06 2000-12-04 新キャタピラー三菱株式会社 Vibration suppression device for vehicle construction machinery
JPH0978633A (en) * 1995-09-13 1997-03-25 Komatsu Ltd Running vibration limiting hydraulic circuit for wheel type construction machine
US5733095A (en) * 1996-10-01 1998-03-31 Caterpillar Inc. Ride control system
DE19711769C2 (en) * 1997-03-21 1999-06-02 Mannesmann Rexroth Ag Hydraulic control arrangement for a mobile work machine, in particular for a wheel loader
JPH1136375A (en) 1997-07-22 1999-02-09 Komatsu Ltd Traveling vibration-control hydraulic circuit in construction machine with wheel
SE511039C2 (en) * 1997-09-30 1999-07-26 Volvo Wheel Loaders Ab Cargo suspension system for damping cargo arm movement
US6167701B1 (en) * 1998-07-06 2001-01-02 Caterpillar Inc. Variable rate ride control
DE19913784A1 (en) * 1999-03-26 2000-09-28 Mannesmann Rexroth Ag Load-sensing hydraulic control arrangement for a mobile machine
US6321534B1 (en) * 1999-07-07 2001-11-27 Caterpillar Inc. Ride control
US6357230B1 (en) * 1999-12-16 2002-03-19 Caterpillar Inc. Hydraulic ride control system

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO03031734A1 *

Also Published As

Publication number Publication date
WO2003031734A1 (en) 2003-04-17
EP1432878B1 (en) 2006-07-12
DE50207525D1 (en) 2006-08-24
DE10148962C1 (en) 2003-02-27
US7117670B2 (en) 2006-10-10
US20040134191A1 (en) 2004-07-15

Similar Documents

Publication Publication Date Title
EP0615583B1 (en) Energy recovering device
DE19956717B4 (en) Hydraulic control device
EP1574626B1 (en) Hydraulic passive suspension system
DE102004012382B4 (en) Hydraulic arrangement
DE102004050294B3 (en) Hydraulic valve arrangement
EP1743981A1 (en) Hydraulic arrangement
EP1450048A1 (en) Valve arrangement
DE4438899C1 (en) Energy recovery installation for work tool
DE102005038333A1 (en) Hydraulic arrangement
EP1003939B1 (en) Hydraulic control device for a mobile machine, especially for a wheel loader
DE102007029355A1 (en) Hydraulic control arrangement
DE4137963C2 (en) Valve arrangement for load-independent control of several hydraulic consumers
DE2335704A1 (en) HYDRAULIC SYSTEM
DE69021706T2 (en) HYDRAULIC CIRCUIT FOR OPERATING A MACHINE.
DE102012001562A1 (en) Valve arrangement for a mobile work machine
WO2010051907A1 (en) Device for compensating for hydraulic effective pressures
DE4342642C2 (en) Electro-hydraulic quick-fall circuit
DE1634886C3 (en)
DE2411051C2 (en) Excavators, such as shovel excavators, shovel loaders or the like.
DE112011104417T5 (en) Independent dosing valve with flow limiter
EP1432878B1 (en) Control device
DE19729870A1 (en) Hydraulic system for working cylinders of construction equipment
DE19548943B4 (en) valve assembly
DE19511522C1 (en) Switching mechanism for hydraulic actuator
EP2896839B1 (en) Device for locking and pressure adjustment

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

17P Request for examination filed

Effective date: 20030821

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR

AX Request for extension of the european patent

Extension state: AL LT LV MK RO SI

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

RBV Designated contracting states (corrected)

Designated state(s): DE FR GB IT

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

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

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 FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT;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: 20060712

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

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

Effective date: 20060725

REF Corresponds to:

Ref document number: 50207525

Country of ref document: DE

Date of ref document: 20060824

Kind code of ref document: P

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

26N No opposition filed

Effective date: 20070413

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

Ref country code: FR

Payment date: 20110517

Year of fee payment: 10

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

Ref country code: GB

Payment date: 20110405

Year of fee payment: 10

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

Ref country code: IT

Payment date: 20110606

Year of fee payment: 10

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

Ref country code: DE

Payment date: 20110708

Year of fee payment: 10

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

Effective date: 20120627

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

Effective date: 20120627

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

Effective date: 20130228

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 50207525

Country of ref document: DE

Effective date: 20130101

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: 20120702

Ref country code: DE

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

Effective date: 20130101

Ref country code: GB

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

Effective date: 20120627