EP1754682B1 - Electrohydraulic device - Google Patents

Electrohydraulic device Download PDF

Info

Publication number
EP1754682B1
EP1754682B1 EP20050017521 EP05017521A EP1754682B1 EP 1754682 B1 EP1754682 B1 EP 1754682B1 EP 20050017521 EP20050017521 EP 20050017521 EP 05017521 A EP05017521 A EP 05017521A EP 1754682 B1 EP1754682 B1 EP 1754682B1
Authority
EP
European Patent Office
Prior art keywords
load
pressure balance
valve
control circuit
pressure
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
EP20050017521
Other languages
German (de)
French (fr)
Other versions
EP1754682A1 (en
Inventor
Martin Dipl.-Ing. Univ. Heusser
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.)
Hawe Hydraulik GmbH and Co KG
Original Assignee
Hawe Hydraulik GmbH and Co KG
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 Hawe Hydraulik GmbH and Co KG filed Critical Hawe Hydraulik GmbH and Co KG
Priority to EP20050017521 priority Critical patent/EP1754682B1/en
Priority to DE200550000989 priority patent/DE502005000989D1/en
Publication of EP1754682A1 publication Critical patent/EP1754682A1/en
Application granted granted Critical
Publication of EP1754682B1 publication Critical patent/EP1754682B1/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66F—HOISTING, LIFTING, HAULING OR PUSHING, NOT OTHERWISE PROVIDED FOR, e.g. DEVICES WHICH APPLY A LIFTING OR PUSHING FORCE DIRECTLY TO THE SURFACE OF A LOAD
    • B66F9/00—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes
    • B66F9/06—Devices for lifting or lowering bulky or heavy goods for loading or unloading purposes movable, with their loads, on wheels or the like, e.g. fork-lift trucks
    • B66F9/075—Constructional features or details
    • B66F9/20—Means for actuating or controlling masts, platforms, or forks
    • B66F9/22—Hydraulic devices or systems
    • 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
    • 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
    • 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
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/003—Systems with load-holding valves
    • 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
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/02—Systems essentially incorporating special features for controlling the speed or actuating force of an output member
    • F15B11/04—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed
    • F15B11/05—Systems essentially incorporating special features for controlling the speed or actuating force of an output member for controlling the speed specially adapted to maintain constant speed, e.g. pressure-compensated, load-responsive
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/30525—Directional control valves, e.g. 4/3-directional control valve
    • F15B2211/3053—In combination with a pressure compensating valve
    • F15B2211/3054—In combination with a pressure compensating valve the pressure compensating valve is arranged between directional control valve and output member
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/31—Directional control characterised by the positions of the valve element
    • F15B2211/3105—Neutral or centre positions
    • F15B2211/3116—Neutral or centre positions the pump port being open in the centre position, e.g. so-called open centre
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/35—Directional control combined with flow control
    • F15B2211/351—Flow control by regulating means in feed line, i.e. meter-in control
    • 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/35—Directional control combined with flow control
    • F15B2211/353—Flow control by regulating means in return line, i.e. meter-out control

Definitions

  • the invention relates to an electro-hydraulic device specified in the preamble of claim 1. Art.
  • a load-holding device is provided as a safety function, and the two-way current regulator also serves as a so-called lowering brake when lowering, which limits the volume flow and thus the retraction speed of the hydraulic consumer.
  • the load holding device is actuated by a magnet so that when adjusting the neutral position of the directional control valve, the load is kept leak-free.
  • lowering the load holding device is switched to non-energized magnet to passage, so that the hydraulic medium flows from the hydraulic consumer through the load holding device, the regulating pressure compensator of the two-way flow regulator and finally the directional control valve to the return.
  • the load-holding device inevitably generates a dynamic pressure even in the flow-through position, which has an undesirable influence on the lowering speed at low when the two-way flow controller is fully open and the hand control valve is in the lowered position Load takes. That is, a small load of the hydraulic load to be lowered at high speed can not be moved at the desired maximum speed. It would have the load-holding device to be formed with an excessively large cross-section, which is expensive and unreasonably claimed a lot of installation space, and yet could not exclude an undesirable residual pressure.
  • JP 2001-040713A EP 1 387 089 A . US 5 325 761 A ,
  • the invention has for its object to provide an electro-hydraulic device of the type mentioned with a manually operable directional control valve, in which the load-holding function is integrated so that it produces no additional unwanted back pressure when lowering a low load.
  • the stacker-tight load-holding function is incorporated directly into the pressure balance and is activated by the arranged in the control circuit of the opening control side of the pressure balance magnetic switching valve, only two pressure-generating components are provided in the flow path from the hydraulic consumer via the pressure balance and the directional control valve to the return, which in any case for the required functions are formed large cross-section that especially when lowering at maximum speed and low load resulting su minim it remains that the desired maximum speed is easily achieved despite low load or only under the load of the hydraulic consumer.
  • the control circuit magnetic switching valve which can be designed physically small and inexpensive due to low control volumes to be controlled, the integration of at least one additional safety function in the electro-hydraulic device without significant additional effort.
  • the magnetic switching valve is always energized when the directional control valve is deflected by hand from the neutral position, so that it then exerts no influence in the control circuit. Only for holding the load, the solenoid switching valve is de-energized, whereby the control function of the pressure compensator abandoned and for the load-holding function is set directly in the pressure compensator.
  • the pressure compensator is formed with three sections, namely the load-holding and non-regulating shut-off section, and a second, together with a third regulating flow section, wherein the third flow section has the maximum flow cross-section with minimal back pressure.
  • the magnetic switching valve is expediently used in the electrohydraulic device in order to automatically set the load holding function in the deactivated state of a functional component of the industrial truck and to switch off the regulating function of the pressure compensator. This precludes inadvertent misuse of the electro-hydraulic device, both for lifting and lowering.
  • the additional safety function is linked to a seat occupancy indicator switch or sensor. If the seat is not occupied by the driver, then the electro-hydraulic device can be operated neither intentionally nor unintentionally, because the load holding function is set and the pressure compensator is rendered inoperative.
  • a circulation pressure compensator is provided between the pressure source and the return, which supplies, so to speak as a load regulator depending on the load, the directional control valve just required volume flow.
  • the solenoid valve is designed to be stacker-tight at least at the connection of the control circuit to the control side of the pressure compensator.
  • Stacker leak has the meaning that only a minimal leakage per unit time is allowed, not comparable to the leakage, for example, in a slide valve.
  • the magnetic switching valve is even formed with a seat valve function at least at the connection of the control circuit to the control side of the pressure compensator, so that the magnetic switching valve in the second non-energized switching position is leaktight leakproof and any lowering of the hydraulic consumer is blocked.
  • the fixed orifice of the two-way flow regulator is defined by the third flow control section of the pressure compensator, which can be designed to be optimally large and therefore produces only minimal back pressure.
  • the diaphragm can be placed as fixed diaphragm in the strand between the pressure balance and the hydraulic consumer and formed with a passage cross-section which generates only minimal back pressure. In this case, branches off from the strand of the control circuit to the control side between the pressure compensator and the fixed orifice, while the control circuit branches off to Zuumbleseite between the fixed orifice and the hydraulic consumer.
  • the two-way flow controller and the magnetic switching valve are expediently combined in a housing block which can be linked to the directional control valve.
  • This housing block can be combined with various manually operable directional control valves as needed and requires little installation space.
  • Fig. 1 illustrates the usual practice in the preparation of an electro-hydraulic device S for a material handling vehicle with a one-sided acted upon by a load hydraulic consumers H, for example a lifting cylinder.
  • a manual control valve which is manually adjustable from the neutral position (holding position) shown in two switching positions (a: lifting, b: lowering) by means of a hand lever 1 is connected to a pressure source P and to a return R.
  • the directional control valve W includes a passage 21, for example, for a so-called non-pressurized circulation in the neutral position and in the sink position.
  • an electrical transducer 2 is provided on the directional control valve W, which reports the deflection of the directional control valve from the neutral position by means of a corresponding signal to a higher-level control, not shown, with the example, a solenoid 10 of an electromagnetically actuated load-holding device EM can be controlled. From the directional control valve W, a lifting, holding and lowering strand 3 leads to the hydraulic consumer H.
  • a two-way flow regulator R is arranged, consisting of a two-section pressure compensator 4 with a diaphragm 5, a control spring 6 and a control circuit from the strand 3 to the control side and a control circuit 8 from the strand 3 to the Zu Kunststoffseite a pressure compensator 4 of the two-way current controller R is formed.
  • the electromagnetic load-holding device EM is arranged between the pressure compensator 4 and the hydraulic consumer H in the strand 3 and formed, for example, as a 2/2-solenoid valve whose solenoid 10 (via a hydraulic pilot control) against the force of a spring 11 a Flow setting.
  • the actuating spring 11 is in non-energized solenoid 10, the load-holding position shown, in which the load of the hydraulic consumer is kept leak-free on a check valve in the seat valve design.
  • the solenoid 10 is energized, for example, by the higher-level control in accordance with the signal of the odometer 2 at least in the lowering position b of the directional control valve W. Since in the flow position of the electromagnetically actuated load-holding device EM, the entire working hydraulic medium must pass, inevitably arises relatively high back pressure, which prevents the achievement of the maximum lowering speed at low load.
  • FIG. 2 The embodiment of the electrohydraulic device according to the invention shown in FIG. 2 has substantially the same functions as the prior art device explained with reference to FIG. 1, so that matching components have the same reference numerals.
  • the pressure compensator 4 of the two-way flow regulator R (for both flow directions) is formed with three sections.
  • the first section 12 is a load-holding section at least in stacker-tight execution in order to realize a load-holding function in the strand 3.
  • the second and third sections 13, 14 are flow control sections, wherein the flow control section 13 includes a variable metering orifice 5 and the maximum flow section flow section 14 cooperates with a fixed orifice 5 'shown in strand 3 between the pressure compensator 4 and the hydraulic consumer H.
  • the two pressure control sections 13, 14 regulate the flow together as a function of the adjustment of the pressure compensator in Aufwinraum Vietnamese under the force of the control spring 6 and the pilot pressure in the control circuit 7 to the control side on the one hand and the pilot pressure in the control circuit 8 to Zuumbleseite on the other.
  • the control circuit 7 branches from strand 3 (in the symbolic dissolved representation in Fig. 2) between the pressure compensator 4 and the fixed orifice 5 'from the strand 3, while the control circuit branches off to the Zuêtseite from the strand 3 between the fixed aperture 5' and the hydraulic consumer H.
  • a 3/2-solenoid valve 15 with a solenoid 17 is included, which is additionally connected to an outlet via a control line 16 to the return R.
  • the solenoid switching valve 15 is, for example, a 3/2-solenoid seat valve 26, the non-energized, as shown, under the force of a spring occupies a second switching position, in which the branched off from the strand 3 control circuit 7 is shut off and the Zuumbleseite the pressure compensator 4 is relieved via the control line 16 to the return.
  • the solenoid switching valve 15 assumes a first switching position, in which the control circuit 7 is continuous and the control line 16 to the return R is locked.
  • the electrical odometer 2 on the directional control valve W is connected to a controller or logic circuit C.
  • the solenoid 17 of the magnetic switching valve 15 is connected via a control line 18, for example, also with the controller C, expediently to achieve an additional safety function via a breaker 19, which is then actuated by a functional component 20, such as a seat occupancy indicator switch or sensor of the industrial truck, and interrupts when the function component is deactivated or the seat is not occupied.
  • control valve W pressure from the pressure source P via the passage 21 of the directional control valve W is reduced.
  • the system is depressurised (non-pressurized circulation).
  • the solenoid 17 is not energized.
  • the Zuumbleseite the pressure compensator 4 is relieved via the control line 16 to the return.
  • the pressure compensator 4 is held by the control spring 16 of the flow position shown.
  • the solenoid switching valve 15 is energized, so that the solenoid 17 sets the first switching position (control circuit 7 continuously, control pressure line 16 blocked).
  • the hydraulic medium flows through the flow section 14 and the fixed panel 5 'to the hydraulic consumer H (lifting).
  • the pressure difference across the fixed orifice 5 ' is tapped, so that the control circuit 7 performs a higher control pressure on the control side than the control pressure tapped off downstream of the fixed orifice 5' in the control circuit 8 on the supply side.
  • the pressure compensator 4 controls the volume flow so that, for example, depending on the deflection of the directional control valve, the hydraulic consumer is moved in the lifting direction at a certain speed, which is kept independent of the load.
  • the pressure compensator 4 operates in its control range.
  • the directional control valve on the hand lever 1 is moved to the neutral position (as shown).
  • the pressure of the pressure source P is reduced via the passage 21.
  • the solenoid 17 is de-energized.
  • the solenoid switching valve 15 goes into the second switching position shown.
  • the control side of the pressure compensator 4 is depressurized to the return R.
  • the pilot pressure in the control circuit 8 switches the pressure balance 4 in its Absperrsetation 12.
  • the load pressure is maintained.
  • the pilot pressure in the control circuit 7 between the strand 3 and the connection of the solenoid valve 15 (here a seat valve 26) is kept free of leaks.
  • the pressure compensator 4 controls with the flow control sections 13, 14, wherein a lowering brake function with limitation of the maximum speed in accordance with the now reversed pressure difference on the fixed aperture 5 'is executed. Since the fixed orifice 5 'belongs to the flow section 14, only slight back pressure is built up, so that the maximum desired speed is achieved even at low load.
  • the breaker 19 interrupts the current application of the switching magnet 17 instantaneously.
  • the pressure compensator 4 is placed on the load holding section 12. The load is held and stops moving.
  • the functional component be a seat occupancy switch or sensor
  • the pressure compensator 4 automatically performs the load holding function with the load holding section 12 so that the hydraulic consumer can neither retract nor can be extended.
  • the solenoid switching valve 15 does not necessarily have to be formed as a seat valve 26. It may be sufficient to use a switching valve (3/2-way valve) in stapler-tight design.
  • Fig. 3 illustrates the concrete, unresolved symbolized representation of the electro-hydraulic device S of Fig. 2, such that the fixed orifice 5 'is contained in the pressure compensator 4, and the control circuit 8 to Zuêtseite between the pressure compensator 4 and the hydraulic consumer H from the strand 3 branches off, while the control circuit 7 branches off to the control side between the pressure compensator 4 and the directional control valve W from the strand 3. Since in FIG. 3 only the fixed diaphragm 5 'can produce a back pressure during lowering, which is predetermined from the outset by the maximum flow cross section, the maximum speed can be achieved without problems even at low load. The outflowing volume flow has only two components to pass to the return R.
  • Fig. 4 illustrates a modified embodiment of the electro-hydraulic device S according to the invention, in which the manual control lever 1 manually adjustable directional control valve W formed in contrast to FIGS. 2 and 3 without Wegmessvorraum and provided a circulation pressure compensator 22 between the pressure source P and the return R. is.
  • the circulation pressure compensator 22 is acted upon from the pressure source via a control circuit 24, and in the opposite direction via a control spring 23 and a control circuit 25 in the lifting switching position of the directional control valve W from a tap 31 via a control line 30 from the fed into the strand 3 consumer pressure is fed.
  • a further control line 29 is guided to the control line 30 via a shuttle valve, which is the load pressure of an optionally further, not shown, the hydraulic consumer reports.
  • the shuttle valve ensures that the respective higher load pressure is brought to the delivery side of the circulation pressure compensator 22. Should no further load pressure control line 29 be provided, the shuttle valve can be omitted.
  • the control circuit 25 is connected to a port 28 of the magnetic switching valve 15 in the control circuit 7, such that in the shown, not energized second switching position of the magnetic switching valve 15 (a 4/2-switching valve in staplerêtr execution) both the control side of the pressure compensator 4 and the Zuumbleseite the circulation pressure compensator 22 are relieved via the control line 16 to the return. This corresponds to the neutral position of the directional control valve W and / or the deactivation of an optionally provided as in Fig. 2 functional component 20 (response of the breaker 19).
  • Fig. 4 is an exploded view of the symbol in which the fixed orifice 5 'of the flow control section 14 is shown in the strand 3 between the pressure compensator 4 and the hydraulic consumer. Accordingly, the control circuits 7, 8 branches off from the strand 3 on both sides of the fixed diaphragm 5 '. In a concrete, not shown embodiment, however, the fixed aperture 5 'is arranged in the pressure compensator 4 itself, analogous to fig. 3. Then, the control circuit 8 branches off from the strand 3 between the pressure compensator 4 and the hydraulic consumer H, while the control circuit 7 branches off from the strand 3 between the pressure compensator 4 and the directional control valve W.
  • the functions are similar as explained with reference to FIGS. 2 and 3, but with the difference that the passage 21 in the neutral position and in the lowering position of the directional control valve relieves the control line 30 to the return, so that the circulation pressure compensator 22 is put into circulation and no supply pressure is present.
  • the solenoid 17 is not energized in the neutral position of the directional control valve W, but in the lifting position and in the lowering position of the directional control valve W.
  • Fig. 4 illustrates a valve block B with a housing 32 in which, for example, of the electro-hydraulic device S in Fig. 3, the pressure compensator 4 and the solenoid switching valve 15 are housed. 33 denotes a knob for the bias of the control spring 6 of the pressure compensator 4.
  • the housing block 32 can be with various manually operated directional control valves W in conventional block design combine.
  • the connections H and R in the housing block 32 are connected to the hydraulic consumer H and the return R.
  • the directional control valve W with the manual operation 1 can be designed with or without control function.

Landscapes

  • Engineering & Computer Science (AREA)
  • General Engineering & Computer Science (AREA)
  • Structural Engineering (AREA)
  • Mechanical Engineering (AREA)
  • Civil Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Transportation (AREA)
  • Fluid Mechanics (AREA)
  • Mining & Mineral Resources (AREA)
  • Chemical & Material Sciences (AREA)
  • Combustion & Propulsion (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Geology (AREA)
  • Fluid-Pressure Circuits (AREA)

Description

Die Erfindung betrifft eine elektrohydraulische Vorrichtung der im Oberbegriff des Patentanspruchs 1 angegebenen Art.The invention relates to an electro-hydraulic device specified in the preamble of claim 1. Art.

Bei solchen einfachen, elektrohydraulischen Vorrichtungen, die hauptsächlich in elektromotorisch oder verbrennungsmotorisch angetriebenen Staplern verwendet werden, ist als Sicherheitsfunktion eine Lasthaltevorrichtung vorgesehen, und dient der Zweiwegestromregler auch beim Senken als sogenannte Senkbremse, die den Volumenstrom und damit die Einfahrgeschwindigkeit des Hydroverbrauchers begrenzt. Die Lasthaltevorrichtung wird durch einen Magneten so betätigt, dass bei Einstellen der Neutralstellung des Wegesteuerventils die Last leckagefrei gehalten wird. Beim Senken wird die Lasthaltevorrichtung bei nicht-bestromtem Magneten auf Durchgang geschaltet, so dass das Hydraulikmedium aus dem Hydroverbraucher durch die Lasthaltevorrichtung, die regelnde Druckwaage des Zweiwegestromreglers und schließlich das Wegesteuerventil zum Rücklauf abströmt. In der Praxis (in Fig. 1 als Blockschaltbild gezeigt) zeigt sich, dass die Lasthaltevorrichtung selbst in der Durchflussstellung unvermeidbar einen Staudruck erzeugt, der bei vollständig aufgesteuertem Zweiwegestromregler und von Hand in die Senken-Stellung gestellten Wegesteuerventil einen unerwünschten Einfluss auf die Senkgeschwindigkeit bei geringer Last nimmt. D.h., eine mit großer Geschwindigkeit abzusenkende, kleine Last des Hydroverbrauchers lässt sich nicht mit der gewünschten maximalen Geschwindigkeit bewegen. Es müsste die Lasthaltevorrichtung mit übermäßig großem Querschnitt ausgebildet werden, was teuer ist und unzweckmäßig viel Einbauraum beansprucht, und dennoch einen, unerwünschten Reststaudruck nicht ausschließen könnte.In such simple, electro-hydraulic devices, which are mainly used in electric motor or internal combustion engine driven trucks, a load-holding device is provided as a safety function, and the two-way current regulator also serves as a so-called lowering brake when lowering, which limits the volume flow and thus the retraction speed of the hydraulic consumer. The load holding device is actuated by a magnet so that when adjusting the neutral position of the directional control valve, the load is kept leak-free. When lowering the load holding device is switched to non-energized magnet to passage, so that the hydraulic medium flows from the hydraulic consumer through the load holding device, the regulating pressure compensator of the two-way flow regulator and finally the directional control valve to the return. In practice (shown as a block diagram in FIG. 1), it is shown that the load-holding device inevitably generates a dynamic pressure even in the flow-through position, which has an undesirable influence on the lowering speed at low when the two-way flow controller is fully open and the hand control valve is in the lowered position Load takes. That is, a small load of the hydraulic load to be lowered at high speed can not be moved at the desired maximum speed. It would have the load-holding device to be formed with an excessively large cross-section, which is expensive and unreasonably claimed a lot of installation space, and yet could not exclude an undesirable residual pressure.

Bei elektrisch oder elektronisch betätigten Wegesteuerventilen von Flurförderfahrzeugen ist es als zusätzliche Sicherheitsfunktion im Falle eines Fehlers in der Elektronik üblich ( DE 103 03 385 A , EP 1 369 598 A ), in den Vorsteuerkreisen der Stromregler im Heben-Strang und im Senken-Strang ein magnetbetätigtes Sicherheitsventil anzuordnen. Jedoch sind die Anforderungen für elektrisch betätigte elektrohydraulische Hubsteuervorrichtungen für Flurförderfahrzeuge anders als für elektrohydraulischen Vorrichtungen mit einem manuell betätigten Wegesteuerventil und einem gemeinsamen Heben-, Halten- und Senken-Strang.In electrically or electronically operated directional control valves of industrial trucks, it is as an additional safety feature in the event of a fault in electronics usual ( DE 103 03 385 A . EP 1 369 598 A ), to arrange a solenoid-operated safety valve in the pilot control circuits of the current regulator in the lift train and in the drain train. However, the requirements for electrically operated electro-hydraulic lift control devices for industrial trucks are different than for electro-hydraulic devices with a manually operated directional control valve and a common lift, hold and lower strand.

Bei einer aus DE 198 14 147 A bekannten Schwenkzylindersteuerungseinrichtug eines Gabelstaplers erfolgt die Richtungs- und Geschwindigkeitssteuerung des doppelseitig beaufschlagbaren Schwenkzylinders mittels eines manuell betätigten Wegesteuerventils. Die kolbenseitige Kammer des Schwenkzylinders ist direkt an das Wegesteuerventil angeschlossen. Die kolbenstangenseitige Kammer des Schwenkzylinders ist hingegen über ein in Abströmrichtung sperrendes Rückschlagventil und ein einseitig gegen Federkraft vorgesteuertes Stromregelventil an das Wegesteuerventil angeschlossen. Der Steuerdruck zur Aufsteuerseite des Stromregelventils wird über ein Proportionalventil eingestellt, das mit einem vom Pumpenversorgungsdruck über ein Druckreduzierventil bereitgestellt wird. Das Proportionalventil ist an die Tankleitung angeschlossen, damit der Vorsteuerdruck zur Aufsteuerseite des Stromregelventils und der Entsperrdruck für das Rückschlagventil bei nicht bestromtern Proportionalventil entlastet sind.At one off DE 198 14 147 A Known Schwenkzylindersteuerungseinrichtug a forklift, the direction and speed control of the double-sided acted upon swing cylinder by means of a manually operated directional control valve. The piston-side chamber of the swing cylinder is connected directly to the directional control valve. The piston rod-side chamber of the swivel cylinder, however, is connected to the directional control valve via a non-return valve blocking in the outflow direction and a flow control valve which is piloted on one side against spring force. The control pressure to the upstream side of the flow control valve is adjusted via a proportional valve provided with one of the pump supply pressure via a pressure reducing valve. The proportional valve is connected to the tank line to relieve pilot pressure to the upstream side of the flow control valve and release pressure to the check valve when the proportional valve is not energized.

Weiterer Stand der Technik ist enthalten in JP 2001-040713A , EP 1 387 089 A , US 5 325 761 A .Further prior art is contained in JP 2001-040713A . EP 1 387 089 A . US 5 325 761 A ,

Der Erfindung liegt die Aufgabe zugrunde, eine elektrohydraulische Vorrichtung der eingangs genannten Art mit einem manuell betätigbarem Wegesteuerventil zu schaffen, bei der die Lasthaltefunktion so integriert ist, dass sie beim Senken einer geringen Last keinen zusätzlichen unerwünschten Staudruck erzeugt.The invention has for its object to provide an electro-hydraulic device of the type mentioned with a manually operable directional control valve, in which the load-holding function is integrated so that it produces no additional unwanted back pressure when lowering a low load.

Die gestellte Aufgabe wird mit den Merkmalen im Patentanspruch 1 gelöst.The object is achieved with the features in claim 1.

Da die staplerdichte Lasthaltefunktion direkt in die Druckwaage eingegliedert ist und durch das im Steuerkreis der Öffnungssteuerseite der Druckwaage angeordnete Magnetschaltventil aktiviert wird, sind im Strömungsweg vom Hydroverbraucher über die Druckwaage und das Wegesteuerventil zum Rücklauf nur zwei staudruckerzeugende Komponenten vorgesehen, die ohnedies für die benötigten Funktionen so großquerschnittig ausgebildet sind, dass der speziell beim Senken mit maximaler Geschwindigkeit und geringer Last entstehende Staudruck su minimal bleibt, dass die gewünschte maximale Geschwindigkeit trotz geringer Last oder nur unter der Last des Hydroverbrauchers problemlos erreicht wird. Zusätzlich ermöglicht das im Steuerkreis angeordnete Magnetschaltventil, das wegen geringer zu beherrschender Steuervolumina kleinbauend und kostengünstig ausgelegt sein kann, die Integration wenigstens einer weiteren Sicherheitsfunktion in die elektrohydraulischen Vorrichtung ohne nennenswerten Mehraufwand. Das Magnetschaltventil wird stets bestromt, wenn das Wegesteuerventil von Hand aus der Neutralstellung ausgelenkt ist, so dass es dann keinen Einfluss im Steuerkreis ausübt. Nur zum Halten der Last wird das Magnetschaltventil stromlos geschaltet, wodurch die Regelfunktion der Druckwaage aufgegeben und dafür die Lasthaltefunktion direkt in der Druckwaage eingestellt wird. Baulich einfach wird die Druckwaage mit drei Sektionen ausgebildet, nämlich der lasthaltenden und nicht regelnd ausgebildeten Absperrsektion, und einer zweiten, gemeinsam mit einem dritten regelnden Durchflusssektion, wobei die dritte Durchflusssektion den maximalen Durchflussquerschnitt mit nur minimalem Staudruck hat.Since the stacker-tight load-holding function is incorporated directly into the pressure balance and is activated by the arranged in the control circuit of the opening control side of the pressure balance magnetic switching valve, only two pressure-generating components are provided in the flow path from the hydraulic consumer via the pressure balance and the directional control valve to the return, which in any case for the required functions are formed large cross-section that especially when lowering at maximum speed and low load resulting su minim it remains that the desired maximum speed is easily achieved despite low load or only under the load of the hydraulic consumer. In addition, arranged in the control circuit magnetic switching valve, which can be designed physically small and inexpensive due to low control volumes to be controlled, the integration of at least one additional safety function in the electro-hydraulic device without significant additional effort. The magnetic switching valve is always energized when the directional control valve is deflected by hand from the neutral position, so that it then exerts no influence in the control circuit. Only for holding the load, the solenoid switching valve is de-energized, whereby the control function of the pressure compensator abandoned and for the load-holding function is set directly in the pressure compensator. Structurally simple, the pressure compensator is formed with three sections, namely the load-holding and non-regulating shut-off section, and a second, together with a third regulating flow section, wherein the third flow section has the maximum flow cross-section with minimal back pressure.

Als weitere Sicherheitsfunktion wird in der elektrohydraulischen Vorrichtung zweckmäßig das Magnetschaltventil benutzt, um in deaktiviertem Zustand einer Funktionskomponente des Flurförderfahrzeugs automatisch die Lasthaltefunktion einzustellen und die Regelfunktion der Druckwaage auszuschalten. Dadurch wird ein unbeabsichtigte Fehlbedienung der elektrohydraulischen Vorrichtung ausgeschlossen, und zwar sowohl zum Heben als auch zum Senken.As a further safety function, the magnetic switching valve is expediently used in the electrohydraulic device in order to automatically set the load holding function in the deactivated state of a functional component of the industrial truck and to switch off the regulating function of the pressure compensator. This precludes inadvertent misuse of the electro-hydraulic device, both for lifting and lowering.

Zweckmäßig ist die zusätzliche Sicherheitsfunktion mit einem Sitzbelegungs-Meldeschalter oder -sensor verknüpft. Ist der Sitz nicht durch den Fahrer belegt, dann kann die elektrohydraulische Vorrichtung weder absichtlich noch unabsichtlich bedient werden, weil die Lasthaltefunktion eingestellt und die Druckwaage funktionslos gemacht ist.Suitably, the additional safety function is linked to a seat occupancy indicator switch or sensor. If the seat is not occupied by the driver, then the electro-hydraulic device can be operated neither intentionally nor unintentionally, because the load holding function is set and the pressure compensator is rendered inoperative.

Bei einer weiteren, zweckmäßigen Ausführungsform ist zwischen der Druckquelle und dem Rücklauf eine Umlaufdruckwaage vorgesehen, die sozusagen als Zulaufregler lastabhängig dem Wegesteuerventil einen gerade benötigten Volumenstrom liefert. Indem die Schließsteuerseite der Umlaufdruckwaage über das Magnetschaltventil in dessen zweiter Schaltstellung zum Rücklauf entlastet wird, kann über die Umlaufdruckwaage kein Beaufschlagungsdruck für den Hydroverbraucher erzeugt werden, was eine gewollte oder ungewollte Bedienung ausschließt und das System entlastet.
In diesem Fall ist es auch zweckmäßig, wenn das Wegesteuerventil einen Durchgang zum Entlasten der Schließsteuerseite der Umlaufdruckwaage zum Rücklauf aufweist und dieser Durchgang in der Neutralstellung und in der Senken-Stellung des Wegesteuerventils offen ist. Die Passivierung der Umlaufdruckwaage kann so sowohl über das Wegesteuerventil als auch über das Magnetschaltventil erfolgen, hingegen beim Senken nur über das Wegesteuerventil.In a further expedient embodiment, a circulation pressure compensator is provided between the pressure source and the return, which supplies, so to speak as a load regulator depending on the load, the directional control valve just required volume flow. By relieving the closing control side of the circulation pressure compensator via the magnetic switching valve in its second switching position to the return, can via the circulation pressure compensator no pressurization pressure for the hydraulic consumer are generated, which excludes a wanted or unwanted operation and relieves the system.
In this case, it is also expedient if the directional control valve has a passage for relieving the closing control side of the circulation pressure compensator to the return and this passage is open in the neutral position and in the lowering position of the directional control valve. The passivation of the circulation pressure compensator can be done both via the directional control valve and via the magnetic switching valve, however, when lowering only via the directional control valve.

Zur sicheren Lasthaltung ist es zweckmäßig, wenn das Magnetschaltventil zumindest am Anschluss des Steuerkreises zur Aufsteuerseite der Druckwaage staplerdicht ausgebildet ist. Staplerdicht hat hierbei die Bedeutung, dass eine nur minimale Leckage pro Zeiteinheit zulässig ist, nicht vergleichbar mit der Leckage beispielsweise bei einem Schieberventil.For safe load maintenance, it is expedient if the solenoid valve is designed to be stacker-tight at least at the connection of the control circuit to the control side of the pressure compensator. Stacker leak has the meaning that only a minimal leakage per unit time is allowed, not comparable to the leakage, for example, in a slide valve.

Besonders zweckmäßig wird das Magnetschaltventil sogar mit einer Sitzventilfunktion zumindest am Anschluss des Steuerkreises zur Aufsteuerseite der Druckwaage ausgebildet, so dass das Magnetschaltventil in der zweiten nicht bestromten Schaltstellung leckagefrei dicht ist und jegliche Senkbewegung des Hydroverbrauchers blockiert wird.Particularly suitably, the magnetic switching valve is even formed with a seat valve function at least at the connection of the control circuit to the control side of the pressure compensator, so that the magnetic switching valve in the second non-energized switching position is leaktight leakproof and any lowering of the hydraulic consumer is blocked.

Bei einer zweckmäßigen Ausführungsform wird die Festblende des Zweiwegestromreglers von der dritten Durchflussregelsektion der Druckwaage definiert, die optimal groß ausgelegt werden kann und demzufolge nur minimalen Staudruck erzeugt. In diesem Fall zweigt vom Strang der Steuerkreis zur Aufsteuerseite zwischen der Druckwaage und dem Wegesteuerventil ab, während der Steuerkreis zur Zusteuerseite zwischen der Druckwaage und dem Hydroverbraucher abzweigt.In an expedient embodiment, the fixed orifice of the two-way flow regulator is defined by the third flow control section of the pressure compensator, which can be designed to be optimally large and therefore produces only minimal back pressure. In this case, branches from the strand of the control circuit to the control side between the pressure compensator and the directional control valve, while the control circuit branches off to Zusteuerseite between the pressure compensator and the hydraulic consumer.

Bei einer alternativen Ausführungsform kann die Blende als Festblende im Strang zwischen der Druckwaage und den Hydroverbraucher platziert und mit einem Durchgangsquerschnitt ausgebildet werden, der nur minimalen Staudruck erzeugt. In diesem Fall zweigt vom Strang der Steuerkreis zur Aufsteuerseite zwischen der Druckwaage und der Festblende ab, während der Steuerkreis zur Zusteuerseite zwischen der Festblende und dem Hydroverbraucher abzweigt.In an alternative embodiment, the diaphragm can be placed as fixed diaphragm in the strand between the pressure balance and the hydraulic consumer and formed with a passage cross-section which generates only minimal back pressure. In this case, branches off from the strand of the control circuit to the control side between the pressure compensator and the fixed orifice, while the control circuit branches off to Zusteuerseite between the fixed orifice and the hydraulic consumer.

Zweckmäßig werden der Zweiwegestromregler und das Magnetschaltventil in einen mit dem Wegesteuerventil verblockbaren Gehäuseblock zusammengefasst. Dieser Gehäuseblock lässt sich mit verschiedenen manuell betätigbaren Wegesteuerventilen nach Bedarf kombinieren und beansprucht wenig Einbauraum.The two-way flow controller and the magnetic switching valve are expediently combined in a housing block which can be linked to the directional control valve. This housing block can be combined with various manually operable directional control valves as needed and requires little installation space.

Anhand der Zeichnung wird der nächstkommende Stand der Technik und werden Ausführungsformen des Erfindungsgegenstandes erläutert. Es zeigen:

Fig. 1
ein Blockschaltbild einer elektrohydraulischen Vorrichtung gemäß Stand der Technik,
Fig. 2
als Blockschaltbild eine erste Ausführungsform einer erfindungsgemäßen elektrohydraulischen Vorrichtung, in aufgelöster Symboldarstellung,
Fig. 3
die Ausführungsform von Fig. 2 in komprimierter Symboldarstellung,
Fig. 4
eine weitere Ausführungsform einer erfindungsgemäßen elektrohydraulischen Vorrichtung, in aufgelöster Symboldarstellung, und
Fig. 5
eine Perspektivansicht eines Gehäuseblocks, in dem zwei Komponenten der Ausführungsformen der Fig. 2 bis 4 zusammengefasst sind.
Reference to the drawing, the closest prior art and embodiments of the subject invention will be explained. Show it:
Fig. 1
a block diagram of an electro-hydraulic device according to the prior art,
Fig. 2
1 is a block diagram of a first embodiment of an electrohydraulic device according to the invention, in exploded symbol representation,
Fig. 3
the embodiment of Fig. 2 in a compressed symbol representation,
Fig. 4
a further embodiment of an electro-hydraulic device according to the invention, in exploded symbol representation, and
Fig. 5
a perspective view of a housing block in which two components of the embodiments of Figs. 2 to 4 are summarized.

Fig. 1 verdeutlicht die in der Praxis übliche Vorgangsweise bei Erstellung einer elektrohydraulischen Vorrichtung S für ein Flurförderfahrzeug mit einem einseitig gegen eine Last beaufschlagbaren Hydroverbraucher H, beispielsweise einem Hubzylinder. Ein manuell aus der gezeigten Neutralstellung (Halten-Stellung) in zwei Schaltstellungen (a: Heben; b: Senken) mittels eines Handhebels 1 manuell verstellbares Wegesteuerventil ist an eine Druckquelle P und an einen Rücklauf R angeschlossen. Das Wegesteuerventil W enthält einen Durchgang 21 beispielsweise für einen sogenannten drucklosen Umlauf in der Neutralstellung und in der Senken-Stellung. Ferner ist ein elektrischer Wegaufnehmer 2 am Wegesteuerventil W vorgesehen, der die Auslenkung des Wegesteuerventils aus der Neutralstellung mittels eines entsprechenden Signals an eine nicht gezeigte, übergeordnete Steuerung meldet, mit der beispielsweise ein Schaltmagnet 10 einer elektromagnetisch betätigbaren Lasthaltevorrichtung EM ansteuerbar ist. Vom Wegesteuerventil W führt ein Heben-, Halten- und Senken-Strang 3 zum Hydroverbraucher H. Zwischen dem Wegesteuerventil W und der elektromagnetischen Lasthaltevorrichtung EM ist im Strang 3 ein Zweiwegestromregler R angeordnet, der aus einer zwei Sektionen aufweisenden Druckwaage 4 mit einer Blende 5, einer Regelfeder 6 und einem Steuerkreis vom Strang 3 zur Aufsteuerseite sowie einem Steuerkreis 8 vom Strang 3 zur Zusteuerseite einer Druckwaage 4 des Zweiwege-Stromreglers R gebildet wird. Die elektromagnetische Lasthaltevorrichtung EM ist zwischen der Druckwaage 4 und dem Hydroverbraucher H im Strang 3 angeordnet und beispielsweise als 2/2-Magnetschaltventil ausgebildet, dessen Schaltmagnet 10 (über eine hydraulische Vorsteuerung) gegen die Kraft einer Stellfeder 11 eine Durchflussstellung einstellt. Die Stellfeder 11 stellt bei nicht-bestromtem Schaltmagneten 10 die gezeigte lasthaltende Stellung ein, in der die Last des Hydroverbrauchers auf einem Rückschlagventil in Sitzventilbauweise leckagefrei gehalten wird. Der Schaltmagnet 10 wird beispielsweise von der übergeordneten Steuerung nach Maßgabe des Signals des Wegmessers 2 zumindest in der Senken-Stellung b des Wegesteuerventils W bestromt. Da in der Durchflussstellung der elektromagnetisch betätigbaren Lasthaltevorrichtung EM das gesamte Arbeits-Hydraulikmedium durchgehen muss, entsteht unvermeidlich relativ hoher Staudruck, der bei geringer Last das Erreichen der maximalen Senken-Geschwindigkeit verhindert. Es sind, in anderen Worten, beim Senken insgesamt drei Komponenten wirksam, die einen Staudruck erzeugen können, nämlich die Lasthaltevorrichtung EM, die Druckwaage 4, und das Wegesteuerventil W selbst. Dabei wirkt sich der Staudruck in der Lasthaltevorrichtung EM am gravierendsten unerwünscht aus. Die Lasthaltefunktion, die sich magnetbetätigt ausschalten lässt, wird jedoch bei solchen elektrohydraulischen Vorrichtungen S mit einem manuell verstellbaren Wegesteuerventil W unbedingt benötigt.Fig. 1 illustrates the usual practice in the preparation of an electro-hydraulic device S for a material handling vehicle with a one-sided acted upon by a load hydraulic consumers H, for example a lifting cylinder. A manual control valve which is manually adjustable from the neutral position (holding position) shown in two switching positions (a: lifting, b: lowering) by means of a hand lever 1 is connected to a pressure source P and to a return R. The directional control valve W includes a passage 21, for example, for a so-called non-pressurized circulation in the neutral position and in the sink position. Further, an electrical transducer 2 is provided on the directional control valve W, which reports the deflection of the directional control valve from the neutral position by means of a corresponding signal to a higher-level control, not shown, with the example, a solenoid 10 of an electromagnetically actuated load-holding device EM can be controlled. From the directional control valve W, a lifting, holding and lowering strand 3 leads to the hydraulic consumer H. Between the directional control valve W and the electromagnetic load-holding device EM in the strand 3, a two-way flow regulator R is arranged, consisting of a two-section pressure compensator 4 with a diaphragm 5, a control spring 6 and a control circuit from the strand 3 to the control side and a control circuit 8 from the strand 3 to the Zusteuerseite a pressure compensator 4 of the two-way current controller R is formed. The electromagnetic load-holding device EM is arranged between the pressure compensator 4 and the hydraulic consumer H in the strand 3 and formed, for example, as a 2/2-solenoid valve whose solenoid 10 (via a hydraulic pilot control) against the force of a spring 11 a Flow setting. The actuating spring 11 is in non-energized solenoid 10, the load-holding position shown, in which the load of the hydraulic consumer is kept leak-free on a check valve in the seat valve design. The solenoid 10 is energized, for example, by the higher-level control in accordance with the signal of the odometer 2 at least in the lowering position b of the directional control valve W. Since in the flow position of the electromagnetically actuated load-holding device EM, the entire working hydraulic medium must pass, inevitably arises relatively high back pressure, which prevents the achievement of the maximum lowering speed at low load. In other words, when lowering, a total of three components are effective, which can generate a back pressure, namely the load-holding device EM, the pressure compensator 4, and the directional control valve W itself. The back pressure in the load-holding device EM has the most serious undesirable effect. However, the load-holding function, which can be turned off magnetically, is absolutely necessary in such electro-hydraulic devices S with a manually adjustable directional control valve W.

Die in Fig. 2 gezeigte Ausführungsform der erfindungsgemäßen elektrohydraulischen Vorrichtung hat im Wesentlichen die gleichen Funktionen wie die anhand Fig. 1 erläuterte Vorrichtung gemäß Stand der Technik, so dass übereinstimmende Komponenten dieselben Bezugszeichen aufweisen.The embodiment of the electrohydraulic device according to the invention shown in FIG. 2 has substantially the same functions as the prior art device explained with reference to FIG. 1, so that matching components have the same reference numerals.

In der elektrohydraulischen Vorrichtung S in Fig. 2 ist die Druckwaage 4 des Zweiwegestromreglers R (für beide Strömungsrichtungen) mit drei Sektionen ausgebildet. Die erste Sektion 12 ist eine Lasthaltesektion zumindest in staplerdichter Ausführung, um eine Lasthaltefunktion im Strang 3 zu realisieren. Die zweiten und dritten Sektionen 13, 14 sind Durchflussregelsektionen, wobei die Durchflussregelsektion 13 eine variable Messblende 5 enthält und die Durchflusssektion 14 mit maximalem Durchflussquerschnitt mit einer im Strang 3 zwischen der Druckwaage 4 und dem Hydroverbraucher H gezeigten Festblende 5' zusammenwirkt. Die beiden Druckregelsektionen 13, 14 regeln den Durchflussstrom gemeinsam abhängig von der Verstellung der Druckwaage in Aufsteuerrichtung unter der Kraft der Regelfeder 6 und dem Vorsteuerdruck im Steuerkreis 7 zur Aufsteuerseite einerseits und dem Vorsteuerdruck im Steuerkreis 8 zur Zusteuerseite andererseits. Der Steuerkreis 7 zweigt vom Strang 3 (in der symbolhaft aufgelösten Darstellung in Fig. 2) zwischen der Druckwaage 4 und der Festblende 5' vom Strang 3 ab, während der Steuerkreis zur Zusteuerseite vom Strang 3 zwischen der Festblende 5' und dem Hydroverbraucher H abzweigt.In the electrohydraulic device S in FIG. 2, the pressure compensator 4 of the two-way flow regulator R (for both flow directions) is formed with three sections. The first section 12 is a load-holding section at least in stacker-tight execution in order to realize a load-holding function in the strand 3. The second and third sections 13, 14 are flow control sections, wherein the flow control section 13 includes a variable metering orifice 5 and the maximum flow section flow section 14 cooperates with a fixed orifice 5 'shown in strand 3 between the pressure compensator 4 and the hydraulic consumer H. The two pressure control sections 13, 14 regulate the flow together as a function of the adjustment of the pressure compensator in Aufsteuerrichtung under the force of the control spring 6 and the pilot pressure in the control circuit 7 to the control side on the one hand and the pilot pressure in the control circuit 8 to Zusteuerseite on the other. The control circuit 7 branches from strand 3 (in the symbolic dissolved representation in Fig. 2) between the pressure compensator 4 and the fixed orifice 5 'from the strand 3, while the control circuit branches off to the Zusteuerseite from the strand 3 between the fixed aperture 5' and the hydraulic consumer H.

Im Steuerkreis 7 zur Zusteuerseite ist zum nicht-regelnden Einstellen der Lasthaltefunktion über die Lasthaltesektion 12 ein 3/2-Magnetschaltventil 15 mit einem Schaltmagneten 17 enthalten, das zusätzlich an einem Auslass über eine Steuerleitung 16 an den Rücklauf R angeschlossen ist. Das Magnet-Schaltventil 15 ist, z.B., ein 3/2-Magnet-Sitzventil 26, das nicht-bestromt, wie gezeigt, unter der Kraft einer Stellfeder eine zweite Schaltstellung einnimmt, , in der der vom Strang 3 abzweigende Steuerkreis 7 abgesperrt ist und die Zusteuerseite der Druckwaage 4 über die Steuerleitung 16 zum Rücklauf entlastet ist. Ist der Schaltmagnet 17 bestromt, dann nimmt das Magnetschaltventil 15 eine erste Schaltstellung ein, in der der Steuerkreis 7 durchgängig ist und die Steuerleitung 16 zum Rücklauf R esperrt wird. Der elektrische Wegmesser 2 am Wegesteuerventil W ist mit einer Steuerung oder Logikschaltung C verbunden. Der Schaltmagnet 17 des Magnetschaltventils 15 ist über eine Steuerleitung 18 beispielsweise ebenfalls mit der Steuerung C verbunden, zweckmäßigerweise zum Erzielen einer zusätzlichen Sicherheitsfunktion über einen Unterbrecher 19, der durch eine Funktionskomponente 20, beispielsweise einen Sitzbelegungsmeldeschalter oder -sensor, des Flurförderfahrzeugs beispielsweise dann betätigt ist und unterbricht, wenn die Funktionskomponente deaktiviert bzw. der Sitz nicht belegt ist.In the control circuit 7 to the Zusteuerseite for non-regulating adjusting the load holding function on the load holding section 12, a 3/2-solenoid valve 15 with a solenoid 17 is included, which is additionally connected to an outlet via a control line 16 to the return R. The solenoid switching valve 15 is, for example, a 3/2-solenoid seat valve 26, the non-energized, as shown, under the force of a spring occupies a second switching position, in which the branched off from the strand 3 control circuit 7 is shut off and the Zusteuerseite the pressure compensator 4 is relieved via the control line 16 to the return. If the switching magnet 17 is energized, then the solenoid switching valve 15 assumes a first switching position, in which the control circuit 7 is continuous and the control line 16 to the return R is locked. The electrical odometer 2 on the directional control valve W is connected to a controller or logic circuit C. The solenoid 17 of the magnetic switching valve 15 is connected via a control line 18, for example, also with the controller C, expediently to achieve an additional safety function via a breaker 19, which is then actuated by a functional component 20, such as a seat occupancy indicator switch or sensor of the industrial truck, and interrupts when the function component is deactivated or the seat is not occupied.

In der gezeigten Neutralstellung des über den Handhebel 1 bedienbaren Wegesteuerventils W wird Druck von der Druckquelle P über den Durchgang 21 des Wegesteuerventils W abgebaut. Das System ist drucklos (druckloser Umlauf). Der Schaltmagnet 17 ist nicht bestromt. Die Zusteuerseite der Druckwaage 4 ist über die Steuerleitung 16 zum Rücklauf entlastet. Die Druckwaage 4 wird von der Regelfeder 16 der gezeigten Durchflussstellung gehalten.In the illustrated neutral position of the operable via the hand lever 1 way control valve W pressure from the pressure source P via the passage 21 of the directional control valve W is reduced. The system is depressurised (non-pressurized circulation). The solenoid 17 is not energized. The Zusteuerseite the pressure compensator 4 is relieved via the control line 16 to the return. The pressure compensator 4 is held by the control spring 16 of the flow position shown.

Zum Heben wird das Wegesteuerventil W von Hand in die Steuerstellung a verstellt. Der Durchgang 21 ist blockiert. Das Magnetschaltventil 15 ist bestromt, so dass der Schaltmagnet 17 die erste Schaltstellung einstellt (Steuerkreis 7 durchgängig; Steuerdruckleitung 16 blockiert). Das Hydraulikmedium strömt durch die Durchflusssektion 14 und die Festblende 5' zum Hydroverbraucher H (Heben). Die Druckdifferenz über die Festblende 5' wird abgegriffen, so dass der Steuerkreis 7 einen höheren Steuerdruck an der Aufsteuerseite führt als der stromab der Festblende 5' abgegriffene Steuerdruck im Steuerkreis 8 an der Zusteuerseite. Die Druckwaage 4 regelt den Volumenstrom so, dass beispielsweise abhängig von der Auslenkung des Wegesteuerventils der Hydroverbraucher in Heberichtung mit einer bestimmten Geschwindigkeit bewegt wird, die lastunabhängig gehalten wird. Die Druckwaage 4 arbeitet in ihrem Regelbereich.To lift the directional control valve W is adjusted by hand in the control position a. The passage 21 is blocked. The solenoid switching valve 15 is energized, so that the solenoid 17 sets the first switching position (control circuit 7 continuously, control pressure line 16 blocked). The hydraulic medium flows through the flow section 14 and the fixed panel 5 'to the hydraulic consumer H (lifting). The pressure difference across the fixed orifice 5 'is tapped, so that the control circuit 7 performs a higher control pressure on the control side than the control pressure tapped off downstream of the fixed orifice 5' in the control circuit 8 on the supply side. The pressure compensator 4 controls the volume flow so that, for example, depending on the deflection of the directional control valve, the hydraulic consumer is moved in the lifting direction at a certain speed, which is kept independent of the load. The pressure compensator 4 operates in its control range.

Zum Anhalten und Halten der Last wird das Wegesteuerventil am Handhebel 1 in die Neutralstellung (wie gezeigt) verstellt. Der Druck der Druckquelle P wird über den Durchgang 21 abgebaut. Der Schaltmagnet 17 ist stromlos. Das Magnetschaltventil 15 geht in die gezeigte zweite Schaltstellung. Die Aufsteuerseite der Druckwaage 4 ist zum Rücklauf R druckentlastet. Der Vorsteuerdruck im Steuerkreis 8 schaltet die Druckwaage 4 in ihre Absperrsektion 12. Der Lastdruck wird gehalten. Auch der Vorsteuerdruck im Steuerkreis 7 zwischen dem Strang 3 und dem Anschluss des Magnetschaltventils 15 (hier einem Sitzventil 26) wird leckagefrei gehalten.To stop and hold the load, the directional control valve on the hand lever 1 is moved to the neutral position (as shown). The pressure of the pressure source P is reduced via the passage 21. The solenoid 17 is de-energized. The solenoid switching valve 15 goes into the second switching position shown. The control side of the pressure compensator 4 is depressurized to the return R. The pilot pressure in the control circuit 8 switches the pressure balance 4 in its Absperrsektion 12. The load pressure is maintained. Also, the pilot pressure in the control circuit 7 between the strand 3 and the connection of the solenoid valve 15 (here a seat valve 26) is kept free of leaks.

Zum Senken wird das Wegesteuerventil W von Hand in die Schaltstellung b verstellt. Der Druck der Druckquelle P wird über den Durchgang 21 abgebaut. Der Schaltmagnet 17 ist bestromt. Die Druckwaage 4 regelt mit den Durchflussregelsektionen 13, 14, wobei eine Senkbremsfunktion mit Begrenzung der maximalen Geschwindigkeit nach Maßgabe der nun umgekehrten Druckdifferenz über die Festblende 5' ausgeführt wird. Da die Festblende 5' zur Durchflusssektion 14 gehört, wird nur geringfügiger Staudruck aufgebaut, so dass die maximal gewünschte Geschwindigkeit selbst bei kleiner Last erzielt wird.To lower the directional control valve W is adjusted by hand in the switching position b. The pressure of the pressure source P is reduced via the passage 21. The solenoid 17 is energized. The pressure compensator 4 controls with the flow control sections 13, 14, wherein a lowering brake function with limitation of the maximum speed in accordance with the now reversed pressure difference on the fixed aperture 5 'is executed. Since the fixed orifice 5 'belongs to the flow section 14, only slight back pressure is built up, so that the maximum desired speed is achieved even at low load.

Sollte während einer Senken-Bewegung oder einer Heben-Bewegung die Funktionskomponente 20 deaktiviert werden, dann unterbricht der Unterbrecher 19 die Strombeaufschlagung des Schaltmagneten 17 augenblicklich. Die Druckwaage 4 wird auf die Lasthaltesektion 12 gestellt. Die Last wird gehalten und bewegt sich nicht weiter.Should the function component 20 be deactivated during a lowering movement or a lifting movement, then the breaker 19 interrupts the current application of the switching magnet 17 instantaneously. The pressure compensator 4 is placed on the load holding section 12. The load is held and stops moving.

Sollte beispielsweise die Funktionskomponente ein Sitzbelegungsschalter oder -sensor sein, dann ist bei nicht belegtem Sitz eine willkürliche oder zufällige Bedienung der elektrohydraulischen Vorrichtung S unmöglich gemacht, da die Druckwaage 4 automatisch die Lasthaltefunktion mit der Lasthaltesektion 12 ausübt, so dass der Hydroverbraucher weder einfahren kann noch ausgefahren werden kann.For example, should the functional component be a seat occupancy switch or sensor, then an arbitrary or accidental operation of the electrohydraulic device S is impossible, as the pressure compensator 4 automatically performs the load holding function with the load holding section 12 so that the hydraulic consumer can neither retract nor can be extended.

Das Magnetschaltventil 15 muss nicht notwendigerweise als Sitzventil 26 ausgebildet werden. Es könnte ausreichen, ein Schaltventil (3/2-Schaltventil) in staplerdichter Ausführung zu verwenden.The solenoid switching valve 15 does not necessarily have to be formed as a seat valve 26. It may be sufficient to use a switching valve (3/2-way valve) in stapler-tight design.

Fig. 3 verdeutlicht die konkrete, nicht aufgelöste symbolisierte Darstellung der elektrohydraulischen Vorrichtung S von Fig. 2, derart, dass die Festblende 5' in der Druckwaage 4 enthalten ist, und der Steuerkreis 8 zur Zusteuerseite zwischen der Druckwaage 4 und dem Hydroverbraucher H vom Strang 3 abzweigt, während der Steuerkreis 7 zur Aufsteuerseite zwischen der Druckwaage 4 und dem Wegesteuerventil W vom Strang 3 abzweigt. Da in Fig. 3 beim Senken nur die Festblende 5' einen Staudruck erzeugen kann, der von vornherein durch den maximalen Durchflussquerschnitt vorbestimmt ist, lässt sich auch bei niedriger Last die maximale Geschwindigkeit problemlos erzielen. Der abströmende Volumenstrom hat bis zum Rücklauf R nur zwei Komponenten zu passieren.Fig. 3 illustrates the concrete, unresolved symbolized representation of the electro-hydraulic device S of Fig. 2, such that the fixed orifice 5 'is contained in the pressure compensator 4, and the control circuit 8 to Zusteuerseite between the pressure compensator 4 and the hydraulic consumer H from the strand 3 branches off, while the control circuit 7 branches off to the control side between the pressure compensator 4 and the directional control valve W from the strand 3. Since in FIG. 3 only the fixed diaphragm 5 'can produce a back pressure during lowering, which is predetermined from the outset by the maximum flow cross section, the maximum speed can be achieved without problems even at low load. The outflowing volume flow has only two components to pass to the return R.

Fig. 4 verdeutlicht eine abgeänderte Ausführungsform der elektrohydraulischen erfindungsgemäßen Vorrichtung S, bei der das mit dem Handhebel 1 manuell verstellbare Wegesteuerventil W im Unterschied zu den Fig. 2 und 3 ohne Wegmessvorrichtung ausgebildet und dafür eine Umlaufdruckwaage 22 zwischen der Druckquelle P und dem Rücklauf R vorgesehen ist. Die Umlaufdruckwaage 22 wird aus der Druckquelle über einen Steuerkreis 24 beaufschlagt, und in der Gegenrichtung über eine Regelfeder 23 und einen Steuerkreis 25, der in der Heben-Schaltstellung des Wegesteuerventils W aus einer Anzapfung 31 über eine Steuerleitung 30 vom in den Strang 3 eingespeisten Verbraucherdruck gespeist wird.Fig. 4 illustrates a modified embodiment of the electro-hydraulic device S according to the invention, in which the manual control lever 1 manually adjustable directional control valve W formed in contrast to FIGS. 2 and 3 without Wegmessvorrichtung and provided a circulation pressure compensator 22 between the pressure source P and the return R. is. The circulation pressure compensator 22 is acted upon from the pressure source via a control circuit 24, and in the opposite direction via a control spring 23 and a control circuit 25 in the lifting switching position of the directional control valve W from a tap 31 via a control line 30 from the fed into the strand 3 consumer pressure is fed.

In Fig. 4 ist zur Steuerleitung 30 über ein Wechselventil eine weitere Steuerleitung 29 geführt, die den Lastdruck eines gegebenenfalls weiteren, nicht gezeigten Hydroverbrauchers meldet. Das Wechselventil stellt sicher, dass der jeweils höhere Lastdruck zur Zusteuerseite der Umlaufdruckwaage 22 gebracht wird. Sollte keine weitere Lastdrucksteuerleitung 29 vorgesehen sein, kann das Wechselventil entfallen. Der Steuerkreis 25 ist an einen Anschluss 28 des Magnetschaltventils 15 im Steuerkreis 7 angeschlossen, derart, dass in der gezeigten, nicht bestromten zweiten Schaltstellung des Magnetschaltventils 15 (ein 4/2-Schaltventil in staplerdichter Ausführung) sowohl die Aufsteuerseite der Druckwaage 4 als auch die Zusteuerseite der Umlaufdruckwaage 22 über die Steuerleitung 16 zum Rücklauf entlastet sind. Dies entspricht der Neutralstellung des Wegesteuerventils W und/oder der Deaktivierung einer gegebenenfalls wie in Fig. 2 vorgesehenen Funktionskomponente 20 (Ansprechen des Unterbrechers 19).In Fig. 4, a further control line 29 is guided to the control line 30 via a shuttle valve, which is the load pressure of an optionally further, not shown, the hydraulic consumer reports. The shuttle valve ensures that the respective higher load pressure is brought to the delivery side of the circulation pressure compensator 22. Should no further load pressure control line 29 be provided, the shuttle valve can be omitted. The control circuit 25 is connected to a port 28 of the magnetic switching valve 15 in the control circuit 7, such that in the shown, not energized second switching position of the magnetic switching valve 15 (a 4/2-switching valve in staplerdichter execution) both the control side of the pressure compensator 4 and the Zusteuerseite the circulation pressure compensator 22 are relieved via the control line 16 to the return. This corresponds to the neutral position of the directional control valve W and / or the deactivation of an optionally provided as in Fig. 2 functional component 20 (response of the breaker 19).

Fig. 4 ist eine aufgelöste Symboldarstellung, in der die Festblende 5' der Durchflussregelsektion 14 im Strang 3 zwischen der Druckwaage 4 und dem Hydroverbraucher gezeigt ist. Dementsprechend zweigen die Steuerkreise 7, 8 an beiden Seiten der Festblende 5' vom Strang 3 ab. In einer konkreten, nicht gezeigten Ausführungsform wird jedoch die Festblende 5' in der Druckwaage 4 selbst angeordnet, analog zu fig. 3. Dann zweigt der Steuerkreis 8 vom Strang 3 zwischen der Druckwaage 4 und dem Hydroverbraucher H ab, während der Steuerkreis 7 vom Strang 3 zwischen der Druckwaage 4 und dem Wegesteuerventil W abzweigt.Fig. 4 is an exploded view of the symbol in which the fixed orifice 5 'of the flow control section 14 is shown in the strand 3 between the pressure compensator 4 and the hydraulic consumer. Accordingly, the control circuits 7, 8 branches off from the strand 3 on both sides of the fixed diaphragm 5 '. In a concrete, not shown embodiment, however, the fixed aperture 5 'is arranged in the pressure compensator 4 itself, analogous to fig. 3. Then, the control circuit 8 branches off from the strand 3 between the pressure compensator 4 and the hydraulic consumer H, while the control circuit 7 branches off from the strand 3 between the pressure compensator 4 and the directional control valve W.

Die Funktionen sind ähnlich wie anhand Fig. 2 bzw. 3 erläutert, jedoch mit dem Unterschied, dass der Durchgang 21 in der Neutralstellung und in der Senken-Stellung des Wegesteuerventils die Steuerleitung 30 zum Rücklauf entlastet, so dass die Umlaufdruckwaage 22 auf Umlauf gestellt ist und kein Versorgungsdruck ansteht. Der Schaltmagnet 17 wird in der Neutralstellung des Wegesteuerventils W nicht bestromt, sondern in der Heben-Stellung und in der Senken-Stellung des Wegesteuerventils W.The functions are similar as explained with reference to FIGS. 2 and 3, but with the difference that the passage 21 in the neutral position and in the lowering position of the directional control valve relieves the control line 30 to the return, so that the circulation pressure compensator 22 is put into circulation and no supply pressure is present. The solenoid 17 is not energized in the neutral position of the directional control valve W, but in the lifting position and in the lowering position of the directional control valve W.

Fig. 4 verdeutlicht einen Ventilblock B mit einem Gehäuse 32, in welchem beispielsweise von der elektrohydraulischen Vorrichtung S in Fig. 3 die Druckwaage 4 und das Magnetschaltventil 15 untergebracht sind. 33 bezeichnet einen Einstellknopf für die Vorspannung der Regelfeder 6 der Druckwaage 4. Der Gehäuseblock 32 lässt sich mit verschiedenen manuell betätigten Wegesteuerventilen W in üblicher Blockbauweise kombinieren. Die Anschlüsse H und R im Gehäuseblock 32 werden an den Hydroverbraucher H bzw. den Rücklauf R angeschlossen. Das Wegesteuerventil W mit der Handbetätigung 1 kann mit oder ohne Regelfunktion ausgelegt werden.Fig. 4 illustrates a valve block B with a housing 32 in which, for example, of the electro-hydraulic device S in Fig. 3, the pressure compensator 4 and the solenoid switching valve 15 are housed. 33 denotes a knob for the bias of the control spring 6 of the pressure compensator 4. The housing block 32 can be with various manually operated directional control valves W in conventional block design combine. The connections H and R in the housing block 32 are connected to the hydraulic consumer H and the return R. The directional control valve W with the manual operation 1 can be designed with or without control function.

Claims (9)

  1. Electrohydraulic device (S) suitable for load-independent movement control of at least one hydraulic consumer (H), which can be acted upon on one side against a load, of an industrial truck, in particular of a stacker driven by an electric motor or an internal combustion engine, by means of a manually actuable directional control valve (W) between a pressure source (P) and a return pass (R) and the hydraulic consumer (H), a two-way current regulator (R) comprising a pressure balance (4) and an orifice (5, 5') as well as a magnetically actuated load-holding device being connected between the directional control valve (W) and the hydraulic consumer (H) in a lifting, lowering and holding branch (3), the load-holding device being split into a load-holding, stacker-tight shut-off section (12) in the pressure balance (4) itself and into a solenoid switching valve (15), which is integrated in the pilot control circuit (7) with respect to the opening side of the pressure balance (4) and can be switched between a first, energized switching position, which opens the pilot control circuit (7), and a second, non-energized switching position, which relieves the opening side of load with respect to the return pass (R), characterized in that the pressure balance (4) is formed by a plurality of sections (12, 13, 14), of which a first section is the load-holding shut-off section (12), which is designed to be nonregulating, and the second and third sections (13, 14) are throughflow-regulating sections, which regulate, at the same time and in the same way, the throughflow current in both directions of flow, wherein, in the second switching position of the solenoid switching valve (15), a pilot control pressure in a pilot control circuit (8), which branches off from the branch (3) to the closing side of the pressure balance (4), switches the pressure balance (4) into its shut-off section (12).
  2. Electrohydraulic device according to Claim 1, characterized in that an interrupter (19) is provided between a solenoid (17) of the solenoid switching valve (15) and at least one functional component (20) of the industrial truck, which interrupter (19) interrupts in the event of a deactivated functional component.
  3. Electrohydraulic device according to Claim 2, characterized in that the interrupter (19) is a seat-occupation signalling switch or sensor of the industrial truck and interrupts the current supply to the solenoid (17) directly or via a higher-order controller (C).
  4. Electrohydraulic device according to Claim 1, characterized in that a rotating pressure balance (22) is provided between the pressure source (P) and the return pass (R), in that the closing side of the rotating pressure balance (22) can be relieved of load with respect to the return pass (R) via the solenoid switching valve (15), which has been switched into the second switching position, and in that the directional control valve (W) has a passage (21) for connecting the closing side of the rotating pressure balance (22) to the return pass (R).
  5. Electrohydraulic device according to Claim 1, characterized in that the solenoid switching valve (15) is designed to be stacker-tight.
  6. Electrohydraulic device according to Claim 1, characterized in that the solenoid switching valve (15) is a seat valve at least with a second switching position which is free of leaks for the control circuit (7).
  7. Electrohydraulic device according to Claim 1, characterized in that the throughflow-regulating sections (13, 14) at least define the fixed orifice (5') of the two-way current regulator (R), and in that the pilot control circuit (7) with respect to the opening side branches off from the branch (3) between the pressure balance (4) and the directional control valve (W), and the pilot control circuit (8) with respect to the closing side of the pressure balance (4) branches off from the branch (3) between the pressure balance (4) and the hydraulic consumer (H).
  8. Electrohydraulic device according to Claim 1, characterized in that the fixed orifice (5') is positioned in the branch (3) between the pressure balance (4) and the hydraulic consumer (H), and in that the pilot control circuit (7) with respect to the opening side branches off from the branch (3) between the pressure balance (4) and the fixed orifice (5'), and the pilot control circuit (8) with respect to the closing side branches off from the branch (3) between the fixed orifice (5) and the hydraulic consumer (H).
  9. Electrohydraulic device according to Claim 1, characterized in that the two-way current regulator (R) and the solenoid switching valve (15) are combined in a housing block (B, 32), which can be blocked by the directional control valve (W).
EP20050017521 2005-08-11 2005-08-11 Electrohydraulic device Active EP1754682B1 (en)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP20050017521 EP1754682B1 (en) 2005-08-11 2005-08-11 Electrohydraulic device
DE200550000989 DE502005000989D1 (en) 2005-08-11 2005-08-11 Electrohydraulic device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP20050017521 EP1754682B1 (en) 2005-08-11 2005-08-11 Electrohydraulic device

Publications (2)

Publication Number Publication Date
EP1754682A1 EP1754682A1 (en) 2007-02-21
EP1754682B1 true EP1754682B1 (en) 2007-07-04

Family

ID=35457398

Family Applications (1)

Application Number Title Priority Date Filing Date
EP20050017521 Active EP1754682B1 (en) 2005-08-11 2005-08-11 Electrohydraulic device

Country Status (2)

Country Link
EP (1) EP1754682B1 (en)
DE (1) DE502005000989D1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102162268A (en) * 2011-04-20 2011-08-24 山重建机(济宁)有限公司 Traveling control device for crawler hydraulic excavator

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3258116B1 (en) * 2016-06-15 2019-12-25 HAWE Hydraulik SE Hydraulic module with pressure-controlled 2-way flow control valve

Family Cites Families (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5325761A (en) * 1991-03-25 1994-07-05 Friedrich Wilh. Schwing Gmbh Switching arrangement for controlling the speed of hydraulic drives
JP3713877B2 (en) * 1997-03-31 2005-11-09 株式会社豊田自動織機 Tilt cylinder speed controller
US5907991A (en) * 1997-12-22 1999-06-01 Caterpillar Inc. Quick drop valve control
DE19923345A1 (en) * 1999-05-21 2000-11-23 Mannesmann Rexroth Ag Electrohydraulic control device for hydraulic lifting cylinder has pressure balancing device coupled to pressure medium recycling line with its valve body acted on by spring with variable equivalent pressure
DE19931142C2 (en) * 1999-07-06 2002-07-18 Sauer Danfoss Holding As Nordb Hydraulic valve arrangement with locking function
JP2001040713A (en) * 1999-08-03 2001-02-13 Shin Caterpillar Mitsubishi Ltd Construction machine with crane function
DE20208577U1 (en) 2002-06-03 2003-12-11 Hawe Hydraulik Gmbh & Co. Kg Electro-hydraulic lift control device for industrial trucks
JP3915622B2 (en) * 2002-07-30 2007-05-16 コベルコ建機株式会社 Load holding device for hydraulic actuator circuit
DE10303385B4 (en) 2003-01-29 2018-11-29 Buchholz Hydraulik Gmbh Control device for a lifting and lowering control
JP2004301214A (en) * 2003-03-31 2004-10-28 Hitachi Constr Mach Co Ltd Hydraulic driving device for work vehicle

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102162268A (en) * 2011-04-20 2011-08-24 山重建机(济宁)有限公司 Traveling control device for crawler hydraulic excavator

Also Published As

Publication number Publication date
DE502005000989D1 (en) 2007-08-16
EP1754682A1 (en) 2007-02-21

Similar Documents

Publication Publication Date Title
EP0546300B1 (en) Electrohydraulic control system
DE102004050294B3 (en) Hydraulic valve arrangement
EP1355065B1 (en) Hydraulic control
DE102006060333B3 (en) Hydraulic valve arrangement
EP2449267B1 (en) Valve arrangement
WO1995032364A1 (en) Control arrangement for at least two hydraulic consumers
EP2294331B1 (en) Hydraulic valve device
DE102004012382A1 (en) Hydraulic arrangement
EP0141301B1 (en) Hydraulic circuit for a load-driving motor
DE10138389A1 (en) Electro-hydraulic device for controlling a double-acting motor
EP2142808B1 (en) Hydraulic control arrangement
DE4108915C2 (en) Hydraulic device for supplying pressure medium to a privileged primary load circuit
EP2268927A1 (en) Control arrangement for controlling a control valve
EP1754682B1 (en) Electrohydraulic device
DE4324177A1 (en) Hydraulic controller, for use in e.g. cranes - contains emergency-stop valve pre-controlling pressure to isolating valve of pressure regulating pump.
DE102012107256B4 (en) Hydraulic lifting drive of a mobile working machine
EP0823559B1 (en) Hydraulic control device
EP2157320B1 (en) Hydraulic device for a hydro motor
EP2157319B1 (en) Hydraulic device for a hydro motor
EP3037678B1 (en) Lifting module
DE3418261C2 (en)
EP2597209B1 (en) Electronic-hydraulic hoisting gear regulation system
EP3436705B1 (en) Control device
DE3905654C2 (en) Hydraulic control device
DE10011016A1 (en) Method and hydraulic steering device for emergency steering with a steering handwheel

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

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

17P Request for examination filed

Effective date: 20060406

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR

AX Request for extension of the european patent

Extension state: AL BA HR MK YU

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 IT SE

REF Corresponds to:

Ref document number: 502005000989

Country of ref document: DE

Date of ref document: 20070816

Kind code of ref document: P

REG Reference to a national code

Ref country code: SE

Ref legal event code: TRGR

AKX Designation fees paid

Designated state(s): DE IT SE

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: 20080407

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

Ref country code: SE

Payment date: 20080825

Year of fee payment: 4

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

Ref country code: SE

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

Effective date: 20090812

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

Ref country code: IT

Payment date: 20080831

Year of fee payment: 4

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 502005000989

Country of ref document: DE

Representative=s name: GROSSE, SCHUMACHER, KNAUER, VON HIRSCHHAUSEN, DE

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 502005000989

Country of ref document: DE

Representative=s name: GROSSE, SCHUMACHER, KNAUER, VON HIRSCHHAUSEN, DE

Ref country code: DE

Ref legal event code: R081

Ref document number: 502005000989

Country of ref document: DE

Owner name: HAWE HYDRAULIK SE, DE

Free format text: FORMER OWNER: HAWE HYDRAULIK GMBH & CO. KG, 81673 MUENCHEN, DE

REG Reference to a national code

Ref country code: DE

Ref legal event code: R082

Ref document number: 502005000989

Country of ref document: DE

Representative=s name: GROSSE, SCHUMACHER, KNAUER, VON HIRSCHHAUSEN, DE

Ref country code: DE

Ref legal event code: R081

Ref document number: 502005000989

Country of ref document: DE

Owner name: HAWE HYDRAULIK SE, DE

Free format text: FORMER OWNER: HAWE HYDRAULIK SE, 81673 MUENCHEN, DE

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

Ref country code: DE

Payment date: 20190828

Year of fee payment: 15

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 502005000989

Country of ref document: DE

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: 20210302

P01 Opt-out of the competence of the unified patent court (upc) registered

Effective date: 20230523