EP0230529A2 - Valve arrangement for hydraulic accumulator - Google Patents

Valve arrangement for hydraulic accumulator Download PDF

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Publication number
EP0230529A2
EP0230529A2 EP86114822A EP86114822A EP0230529A2 EP 0230529 A2 EP0230529 A2 EP 0230529A2 EP 86114822 A EP86114822 A EP 86114822A EP 86114822 A EP86114822 A EP 86114822A EP 0230529 A2 EP0230529 A2 EP 0230529A2
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EP
European Patent Office
Prior art keywords
valve
pressure
shut
control
arrangement according
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP86114822A
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German (de)
French (fr)
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EP0230529A3 (en
EP0230529B1 (en
Inventor
Gerald Lexen
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.)
MAN Truck and Bus SE
Original Assignee
MAN Nutzfahrzeuge AG
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Publication date
Application filed by MAN Nutzfahrzeuge AG filed Critical MAN Nutzfahrzeuge AG
Priority to AT86114822T priority Critical patent/ATE72693T1/en
Publication of EP0230529A2 publication Critical patent/EP0230529A2/en
Publication of EP0230529A3 publication Critical patent/EP0230529A3/en
Application granted granted Critical
Publication of EP0230529B1 publication Critical patent/EP0230529B1/en
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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B1/00—Installations or systems with accumulators; Supply reservoir or sump assemblies
    • F15B1/02—Installations or systems with accumulators
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/042—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure
    • F15B2013/0428—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by fluid pressure with switchable internal or external pilot pressure source
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/87169—Supply and exhaust
    • Y10T137/87193—Pilot-actuated
    • Y10T137/87209—Electric

Definitions

  • the invention relates to a valve arrangement for connecting a hydraulic pressure accumulator to a hydraulic pump or hydraulic working machine.
  • shut-off valve is arranged, which must be completely leak-tight, in order to prevent the hydraulic machine from being accidentally pressurized and starting, in particular when the hydraulic machine is based on the displacement principle works because a leaking shut-off valve could build up enough pressure over a long period of time to start this machine.
  • the shut-off valve was previously designed as a manually operated shut-off valve that had to be opened and closed as required.
  • shut-off valve In order to achieve an even better use of the excess energy in stationary systems or vehicles, especially if there are frequent changes in the operating state, it is necessary to integrate the shut-off valve in a control or regulating system and no longer by hand, but by Control signals. As tests by the applicant have shown, the coupling of a servomotor with a conventional shut-off valve leads to inadequate results because either the actuating forces become impermissibly high or the switching time of the shut-off valve is too long.
  • the invention has for its object to further develop the known valve arrangement mentioned at the outset such that it can be controlled by means of a control signal without impairing operational safety and is capable of responding quickly to this control signal.
  • shut-off valve arranged in a working line is not actuated directly, but rather by means of a leak-free control valve, the actuation of which requires only relatively small forces.
  • controlled a hydraulic control circuit which in turn provides the actuating forces required to operate the shut-off valve.
  • the shut-off valve has a control cylinder in which an actuating piston is slidably received.
  • This actuating piston carries a valve body that can be hermetically sealed against a valve seat and always seals leak-free even against extremely high pressure drops, provided that a sufficiently high control pressure acts on the actuating piston, because the pressure prevailing on both sides of the valve seat seeks to actuate the actuating piston in this way to move the valve body up from the valve seat.
  • the two outputs of the shut-off valve according to the invention are connected on both sides of the valve seat to a shuttle valve, the third connection of which is connected to the control cylinder of the shut-off valve.
  • the pressure drop that drives the shuttle valve corresponds to the pressure drop across the shut-off valve, with the higher pressure applied to it being applied by the shuttle valve to the control cylinder, so that the pressure on the control piston is always sufficient to ensure that the valve body is sufficient press firmly against the valve seat.
  • the control piston is leak-free sealing in the control cylinder according to a preferred embodiment of the invention, however, that connection of the shut-off valve which is separated from the interior of the control cylinder only by the control piston is connected to the pressure accumulator; as long as the shut-off valve is closed, in particular during those times when the device equipped with the valve arrangement according to the invention is not used, there is therefore no pressure drop across the actuating piston, so that the shut-off valve can also shut off leak-tight over an arbitrary long period of time, as was the case with the previously used manual shut-off valves.
  • shut-off valve To open the shut-off valve there is a leak-free, remotely operated control valve between its control cylinder and the shuttle valve arranged, which in its rest position establishes the connection between the shuttle valve and the control cylinder, on the other hand shuts off the shuttle valve in the working position and relieves the control cylinder against a tank or reservoir.
  • a throttle is arranged between the control cylinder and the control valve or this and the tank or the storage container, which ensures that the control cylinder, in which the above-mentioned high pressure of over 400 bar can prevail, is not approximately is released explosively, which could lead to damage in the control valve, in the lines and also in the shut-off valve.
  • the shut-off valve is designed as a 2/2-way valve in a cartridge design; such a standard valve fulfills all of the above requirements for the shut-off valve according to the invention, forms a ready-to-install unit and can be replaced with another, similar valve with little effort if necessary, e.g. if Safety regulations should prescribe the regular replacement of the shut-off valve.
  • control valve is designed as a directional seat valve, which preferably has an electromagnetic drive.
  • a valve has a valve seat which, when the valve is at rest, hermetically seals its connection to the tank seals so that the control pressure transmitted by the control valve in this operating state cannot escape to the tank.
  • the control valve is also designed so that any pressure forces that occur are directed perpendicular to the movement of its valve body, so that only relatively small actuating forces are required. Because of the small, required channel cross section, the valve body of the control valve only has to travel a relatively short switching distance, so that an electromagnet as an actuator for the control valve is completely sufficient.
  • a pressure measuring point with a pressure sensor or for receiving such a valve is arranged on both sides of the shut-off valve, preferably in the respective control line to the shuttle valve; Via these two pressure measuring points, every pressure relevant for operation and operational safety can be taken off, e.g. the supply pressure in the accumulator, the delivery pressure of the hydraulic machine working as a pump and the like. More. When the shut-off valve is closed, the pressure drop measured must remain constant. If this is not the case, then there is a fault.
  • the two measuring points can be equipped with a device which takes remedial measures in the event of such a fault and / or triggers an alarm.
  • a shut-off throttle is arranged between the pressure accumulator and the tank, which can optionally be provided with a servomotor.
  • This shut-off throttle is used to safely relieve the pressure in the reservoir towards the tank, which is necessary, for example, when repair or maintenance work on the pressure reservoir or on the valve arrangement has to be carried out. It is also possible to connect a servomotor assigned to the shut-off throttle to a monitoring device which is connected to the two measuring points mentioned above, so that the pressure accumulator is automatically emptied when a fault occurs.
  • valves and throttles of the arrangement according to the invention is accommodated in a common block.
  • This block preferably accommodates all elements of the arrangement according to the invention.
  • the various working and control lines of the arrangement according to the invention are thus formed by bores, so that the risk of damage to a connecting line is excluded.
  • This block can advantageously be flanged directly to the pressure accumulator; however, it is equally possible to attach this block wherever this is particularly advantageous for spatial reasons.
  • the block does not have to be easily accessible from the outside, as was the case with the manually operated shut-off valve of the known arrangement mentioned at the beginning.
  • a pressure limiting valve is preferably also arranged, which connects the pressure accumulator to the tank and has the purpose of automatically lowering this excess pressure to a permissible value in the event of an unacceptable excess pressure in the pressure accumulator.
  • Such an impermissible excess pressure can be brought about, for example, by mechanical deformation of the pressure accumulator or its heating. It is thus possible to mount the pressure accumulator together with the valve arrangement according to the invention in a vehicle even at locations where it is exposed to the sun's rays or other heating. Furthermore, the latter configuration ensures that the pressure accumulator does not burst in the event of an accident.
  • the invention thus creates a compact shut-off block with safety functions for hydraulic accumulators with a blocking position, a continuous position and the possibility of emptying the accumulator directly into the oil tank via a blocking throttle.
  • the control pressure for controlling the actual shut-off valve which is preferably designed as a 2/2-way valve in a cartridge construction, is directly derived from the connections for the accumulator or the connected hydraulic unit taken, the higher of the two pressures being selected in order to achieve a reliable holding effect. Furthermore, measuring connections for regulation, control or monitoring are provided.
  • Both the 2/2-way valve in cartridge design and the directional seat valve controlling this are each absolutely sealed when closed, so that any pressure drop due to leakage is reliably avoided even over a long period of time.
  • the shut-off block according to the invention is thus very compact and simple, can be attached to the pressure vessel as well as anywhere in a vehicle, and the valve can be operated remotely, so that the shut-off block according to the invention can be used for the electro-hydraulic control of the accumulator hydraulics is suitable.
  • the simple structure also guarantees safe operation.
  • shut-off block according to the invention is shown schematically.
  • the shut-off block 5 shown has three hydraulic connections, namely the connection P for a hydraulic unit designed either as a pump or working machine, the connection S for a high-pressure or low-pressure accumulator and the connection T for a tank or reservoir.
  • a 2/2-way valve C in a cartridge design is arranged, which has a control cylinder 6.
  • an actuating piston 9 is arranged in a sealing and movable manner and carries a valve body 10 on its side facing away from the pressure chamber of the control cylinder 6.
  • This valve body 10 is set up in the end position shown in the drawing opposite a valve seat 11 seal leak-free.
  • the valve seat 11 divided into the interior of the valve C into a first space 7 with a connection B adjacent to the actuating piston 9 and a second space 8 with a connection A.
  • the connection B is connected to the storage connection S by a working line 3 during the connection A is connected via a working line 4 to the connection P for the hydraulic unit.
  • a spring is preferably provided in valve C, which presses the actuating piston 9 and thus the valve body 10 in abutment against the valve seat 11.
  • the working line 4 is connected via a control line 1 to the one input of a shuttle valve WV, the other input of which is connected to the working line 3 via a control line 2.
  • the two control lines 1 and 2 and thus also the respective working line 4 and 3 are each formed with a measuring connection M 'or M ⁇ , on which a pressure sensor is arranged.
  • the output of the shuttle valve WV is connected to the control cylinder 6 of the valve C via a further control line 10.
  • the shuttle valve WV has a valve body, which blocks that of the two inputs of the valve WV, which has the lower pressure of both inputs, so that the control cylinder 6 can always be connected to that working line 3 or 4, in each of which the higher one Pressure prevails. Provision is therefore always made that when the control cylinder 6 is pressurized, it is so high that the valve body 10 of the valve C remains pressed against the valve seat 11 in a sealing manner.
  • the directional seat valve W connects the two branches of the control line 10, between which the directional seat valve W is arranged.
  • a discharge line 11 which connects the directional seat valve W to the connection T for the reservoir, is blocked off leak-free by an absolutely tight valve seat seal.
  • control cylinder 6 is emptied via the port T and is therefore free of pressure, so that only the pressure prevailing in the interior spaces 7 and 8 of the valve C of the valve C acts on it, displacing this control piston 9 in the drawing and thus the Valve body 10 lifts off the valve seat 11, as a result of which the interiors 7 and 8 and thus the connections B and A of the valve are connected to one another and hydraulic work fluid can flow unhindered between the connections S and P via the working lines 3 and 4.
  • a first throttle DR ' is provided, and between this and the tank port T, a second throttle DR ⁇ is provided in line 11.
  • These two throttles are designed to prevent the explosion-like pressure drop in the control cylinder 6 of the shut-off valve C and to enable the controlled but rapid opening of the shut-off valve C at a predetermined speed or in a predetermined opening time.
  • the shut-off block preferably also has a pressure relief valve DB, which the working line 3 with the relief line 11 and thus the connections S and T with each other.
  • This pressure relief valve DB relieves any pressure increases caused by external influences (e.g. temperature, deformation, etc.), which can occur particularly in the event of an accident. If the increase in pressure in the pressure accumulator cannot take on a critical value due to external influences, the valve DB can be omitted.
  • a shut-off throttle D is arranged, through the opening of which the working line 3 can also be connected to the discharge line 11 and thus the connection S for the pressure accumulator to the connection T for the storage container. It is thus possible to lower the pressure accumulator by opening the shut-off throttle D and to make it pressure-free. This is necessary, for example, if repairs or a change in the hydraulic oil have to be carried out.
  • the shut-off throttle D can be operated remotely and can be coupled to a monitoring device or a sensor. For example, it is possible to couple the shut-off throttle D with a cover closing the arrangement in such a way that when the cover is removed, the pressure accumulator is emptied for safety reasons. It is also possible to provide the shut-off throttle D with an easily accessible handle, via which e.g. the pressure accumulator can be released after an accident.

Abstract

A valve arrangement for connecting a hydraulic machine, such as a pump or a motor, with a pressure accumulator in which a conventional manual shutoff valve is replaced by a leak-proof pressure controlled valve whose operating pressure signal is supplied by a shuttle valve from that one of two ports of the pressure controlled valve at which the higher pressure prevails at a given time. The pressure controlled valve is supplied with fluid under pressure by way of a leak-proof remote controlled slide valve.

Description

Die Erfindung betrifft eine Ventilanordnung zum Anschluß eines hy­draulischen Druckspeichers an eine hydraulische Pumpe bzw. hydrau­lische Arbeitsmaschine.The invention relates to a valve arrangement for connecting a hydraulic pressure accumulator to a hydraulic pump or hydraulic working machine.

Es ist bekannt, mittels einer wahlweise als Pumpe betreibbaren hy­draulischen Arbeitsmaschine in einer Anlage anfallende, überschüs­sige kinetische Energie in potentielle Energie umzuwandeln und in einem Hochdruck- oder Niederdruckspeicher zu sammeln, wobei diese potentielle Energie bei Bedarf dem Speicher wieder entnommen wer­den kann und die dann als Arbeitsmaschine wirksame hydraulische Maschine treiben kann.It is known to convert excess kinetic energy accumulated in a system into potential energy by means of an optionally operable hydraulic working machine in a system and to collect it in a high-pressure or low-pressure accumulator, this potential energy being able to be taken from the accumulator as needed and then as Machine can drive effective hydraulic machine.

Zwischen dieser hydraulischen Maschine und dem Druckspeicher ist ein Absperrventil angeordnet, welches völlig leckagedicht sein muß, um in jedem Falle zu verhindern, daß die hydraulische Maschine versehent­lich mit Druck beaufschlagt wird und damit anläuft, und zwar insbe­sondere dann, wenn die hydraulische Machine nach dem Verdrängungs­prinzip arbeitet, da sich durch ein undichtes Absperrventil über längere Zeit hinweg ein genügender Dru aufbauen könnte, um diese Maschine in Gang zu setzen.Between this hydraulic machine and the pressure accumulator, a shut-off valve is arranged, which must be completely leak-tight, in order to prevent the hydraulic machine from being accidentally pressurized and starting, in particular when the hydraulic machine is based on the displacement principle works because a leaking shut-off valve could build up enough pressure over a long period of time to start this machine.

Das Absperrventil war bisher als von Hand betätigbarer Absperrhahn ausgebildet, der je nach Bedarf geöffnet und geschlossen werden mußte.The shut-off valve was previously designed as a manually operated shut-off valve that had to be opened and closed as required.

Mit einem solchen handbetätigten Absperrhahn ist eine nur verhältnis­mäßig grobe Steuerung möglich, zumal jedes Öffnen oder Schließen einen erheblichen Zeitaufwand benötigt.With such a manually operated shut-off valve, only a relatively rough control is possible, especially since each opening or closing takes a considerable amount of time.

Ist der genannte Druckspeicher an einem Fährzeug angebracht und soll er für den Fahrbetrieb eingesetzt werden, so ist die Verwendung eines solchen handbetätigten Absperrventils vollends ausgeschlossen, da des­sen Betätigung den Fahrer zu sehr in Anspruch nehmen würde.If the pressure accumulator mentioned is attached to a vehicle and is to be used for driving, the use of such a manually operated shut-off valve is completely ruled out, since its actuation would take up too much strain on the driver.

Um bei stationären Anlagen oder Fahrzeugen eine noch bessere Nutzung der überschüssigen Energie zu erreichen, und zwar besonders dann, wenn häufige Wechsel im Betriebszustand vorliegen, ist es erforder­lich, das Absperrventil in ein Steuer- oder Regelsystem zu integrie­ren und nicht mehr von Hand, sondern durch Steuersignale anzusteuern. Wie Versuche der Anmelderin ergeben haben, führt aber die Koppelung eines Stellmotors mit einem herkömmlichen Absperrventil zu nur unzu­länglichen Ergebnissen, weil entweder die Stellkräfte unzulässig hoch werden oder die Schaltzeit des Absperrventils zu lang ist.In order to achieve an even better use of the excess energy in stationary systems or vehicles, especially if there are frequent changes in the operating state, it is necessary to integrate the shut-off valve in a control or regulating system and no longer by hand, but by Control signals. As tests by the applicant have shown, the coupling of a servomotor with a conventional shut-off valve leads to inadequate results because either the actuating forces become impermissibly high or the switching time of the shut-off valve is too long.

Da am Absperrventil im Betrieb Drücke von mehr als 400 bar auftreten können, kann auch ein herkömmliches, fernsteuerbares Schieberventil nicht verwendet werden, da es nicht ausreichend leckagesicher ist und da außerdem je nach Bauart außerordentlich hohe Kräfte auf den Stell­antrieb einwirken können.Since pressures of more than 400 bar can occur on the shut-off valve during operation, a conventional, remotely controllable slide valve cannot be used either, since it is not sufficiently leak-proof and, depending on the design, extraordinarily high forces can act on the actuator.

Ausgehend von diesem Stand der Technik liegt der Erfindung die Auf­gabe zugrunde, die eingangs genannte, bekannte Ventilanordnung dahin­gehend weiterzubilden, daß sie ohne Beeinträchtigung der Beetriebssicher­heit mittels eines Steuersignals ansteuerbar ist und imstande ist, auf dieses Steuersignal rasch anzusprechen.Based on this prior art, the invention has for its object to further develop the known valve arrangement mentioned at the outset such that it can be controlled by means of a control signal without impairing operational safety and is capable of responding quickly to this control signal.

Diese Aufgabe wird durch die Merkmale des Anspruchs 1 gelöst.This object is solved by the features of claim 1.

Hierbei liegt die Lösung im Prinzip darin, daß nicht das in einer Ar­beitsleitung aneordnete Absperrventil unmittelbar angesteuert wird, sondern es wird mittels eines leckagefreien Steuerventils, zu dessen Ansteuerung nur verhältnismäßig geringe Kräfte erforderlich sind, ein hydraulischer Steuerkreis angesteuert, der seinerseits die zum Betätigen des Absperrventiles erforderlichen Stellkräfte liefert.In principle, the solution here is that the shut-off valve arranged in a working line is not actuated directly, but rather by means of a leak-free control valve, the actuation of which requires only relatively small forces. controlled a hydraulic control circuit, which in turn provides the actuating forces required to operate the shut-off valve.

Das Absperrventil weist erfindungsgemäß einen Steuerzylinder auf, in welchem ein Stellkolben verschieblich aufgenommen ist. Dieser Stell­kolben trägt einen Ventilkörper, der hermetisch dichtend gegen einen Ventilsitz anlegbar ist und auch gegenüber äußerst hohem Druckgefälle stets leckagefrei abdichtet, vorausgesetzt, es wirkt ein ausreichend hoher Steuerdruck auf den Stellkolben ein, denn die beiderseits des Ventilsitzes vorherrschenden Drücke trachten danach, den Stellkolben so zu verschieben, daß der Ventilkörper vom Ventilsitz abhebt.According to the invention, the shut-off valve has a control cylinder in which an actuating piston is slidably received. This actuating piston carries a valve body that can be hermetically sealed against a valve seat and always seals leak-free even against extremely high pressure drops, provided that a sufficiently high control pressure acts on the actuating piston, because the pressure prevailing on both sides of the valve seat seeks to actuate the actuating piston in this way to move the valve body up from the valve seat.

Um in jedem Fall einen ausreichenden Steuerdruck bereitzustellen, sind erfindungsgemäß die beiden Ausgänge des erfindungsgemäßen Absperrven­tiles beiderseits des Ventilsitzes jeweils mit einem Wechselventil ver­bunden, dessen dritter Anschluß mit dem Steuerzylinder des Absperr­ventils verbunden ist. Das das Wechselventil ansteuernde Druckgefälle entspricht dem über das Absperrventil hinweg vorliegende Druckgefälle, wobei der jeweils höhere, an diesem anliegende Druck vom Wechselventil an den Steuerzylinder angelegt wird.Es wirkt somit auf den Stellkolben stets ein solcher Druck ein, der ausreicht, um den Ventilkörper aus­reichend fest gegen den Ventilsitz anzudrücken.In order to provide a sufficient control pressure in each case, the two outputs of the shut-off valve according to the invention are connected on both sides of the valve seat to a shuttle valve, the third connection of which is connected to the control cylinder of the shut-off valve. The pressure drop that drives the shuttle valve corresponds to the pressure drop across the shut-off valve, with the higher pressure applied to it being applied by the shuttle valve to the control cylinder, so that the pressure on the control piston is always sufficient to ensure that the valve body is sufficient press firmly against the valve seat.

Der Stellkolben ist leckagefrei dichtend im Steuerzylinder geführt gemäß einer bevorzugten Ausgestaltung der Erfindung ist aber jener An­schluß des Absperrventiles, der vom inneren des Steuerzylinders nur durch den Stellkolben getrennt ist, mit dem Druckspeicher verbunden; solange das Absperrventil geschlossen ist, also besonders während jener Zeiten, in denen die mit der erfindungsgemäßen Ventilanordnung aus­gestattete Einrichtung nicht benutzt wird, tritt somit über den Stell­kolben hinweg keinerlei Druckgefälle auf, so daß das Absperrventil über einen beliebig langen Zeitraum hinweg ebenso leckagedicht ab­sperren kann, wie dies bei den bisher verwendeten handbetätigten Ab­sperrventilen der Fall war.The control piston is leak-free sealing in the control cylinder according to a preferred embodiment of the invention, however, that connection of the shut-off valve which is separated from the interior of the control cylinder only by the control piston is connected to the pressure accumulator; as long as the shut-off valve is closed, in particular during those times when the device equipped with the valve arrangement according to the invention is not used, there is therefore no pressure drop across the actuating piston, so that the shut-off valve can also shut off leak-tight over an arbitrary long period of time, as was the case with the previously used manual shut-off valves.

Zum Öffnen des Absperrventiles ist zwischen dessen Steuerzylinder und dem Wechselventil ein leckagefreies, fernbetätigbares Steuerventil angeordnet, das in seiner Ruhelage die Verbindung zwischen dem Wech­selventil und dem Steuerzylinder herstellt, dagegen in der Arbeits­lage zum Wechselventil hin absperrt und den Steuerzylinder gegen einen Tank oder Vorratsbehälter hin entlastet.To open the shut-off valve there is a leak-free, remotely operated control valve between its control cylinder and the shuttle valve arranged, which in its rest position establishes the connection between the shuttle valve and the control cylinder, on the other hand shuts off the shuttle valve in the working position and relieves the control cylinder against a tank or reservoir.

In diesem Steuerventil herrschen zwar, wie oben erwähnt, die gleichen hohen Drücke wie im Absperrventil, aber der zu steuernde Durchsatz an hydraulischer Flüssigkeit ist nur gering, da diese nur zum Ansteuern des Absperrventiles verwendet wird. Daher ist es möglich, ein solches Ventil mit einem Stellantrieb zu versehen, der durch ein Steuersignal ansteuerbar ist um in ausreichend kurzer Zeit zuverlässig das Ventil betätigt. Da das Ventil eine deffinierte Ruhelage aufweist, in welcher es den Steuerzylinder des Absperrventils mit dem Wechselventil verbin­det, ist bei Ausfall der Steuerung Vorsorge getroffen, daß der Druck­speicher abgesperrt wird.In this control valve, as mentioned above, there are the same high pressures as in the shut-off valve, but the throughput of hydraulic fluid to be controlled is only low, since this is only used to actuate the shut-off valve. It is therefore possible to provide such a valve with an actuator which can be controlled by a control signal in order to reliably actuate the valve in a sufficiently short time. Since the valve has a defined, inoperative position, in which it connects the control cylinder of the shut-off valve with the shuttle valve, precaution is taken in the event of a control failure that the pressure accumulator is shut off.

Gemäß bevorzugter Ausgestaltungen der Erfindung ist zwischen dem Steu­erzylinder und dem Steuerventil bzw. diesem und dem Tank oder dem Vorratsbehälter eine Drossel angeordnet, die dafür sorgt, daß der Steuerzylinder, in dem der bereits oben erwähnte hohe Druck von über 400 bar herrschen kann, nicht etwa explosionsartig entlastet wird, was zu Schäden im Steuerventil, in den Leitungen und auch im Absperr­ventil führen könnte.According to preferred embodiments of the invention, a throttle is arranged between the control cylinder and the control valve or this and the tank or the storage container, which ensures that the control cylinder, in which the above-mentioned high pressure of over 400 bar can prevail, is not approximately is released explosively, which could lead to damage in the control valve, in the lines and also in the shut-off valve.

Das Absperrventil ist gemäß einer bevorzugten Ausgestaltung der Er­findung als 2/2-Wegeventil in Cartridge-Ausführung ausgebildet; ein solches serienmäßiges Ventil erfüllt alle obengenannten Anforderungen an das erfindungsgemäße Absperrventil, bildet eine einbaufertige Ein­heit und kann mit geringem Aufwand ggf. gegen ein anderes, gleichar­tiges Ventil ausgewechselt werden, wenn z.B. Sicherheitsvorschriften die turnusmäßige Erneuerung des Absperrventils vorschreiben sollten.According to a preferred embodiment of the invention, the shut-off valve is designed as a 2/2-way valve in a cartridge design; such a standard valve fulfills all of the above requirements for the shut-off valve according to the invention, forms a ready-to-install unit and can be replaced with another, similar valve with little effort if necessary, e.g. if Safety regulations should prescribe the regular replacement of the shut-off valve.

Gemäß einer weiteren Ausgestaltung der Erfindung ist das Steuerventil als Wegesitzventil ausgebildet, das bevorzugt einen elektromagnetischen Antrieb aufweist. Ein solches Ventil weist einen Ventilsitz auf, der in der Ruhelage des Ventils dessen Anschluß zum Tank hin hermetisch abdichtet, so daß der in diesem Betriebszustand vom Steuerventil über­tragene Steuerdruck nicht zum Tank hin entweichen kann.According to a further embodiment of the invention, the control valve is designed as a directional seat valve, which preferably has an electromagnetic drive. Such a valve has a valve seat which, when the valve is at rest, hermetically seals its connection to the tank seals so that the control pressure transmitted by the control valve in this operating state cannot escape to the tank.

Das Steuerventil ist ferner so ausgebildet, daß etwa auftretende Druck­kräfte senkrecht zur Bewegung seines Ventilkörpers gerichtet sind, so daß nur verhältnismäßig geringe Stellkräfte erforderlich sind. We­gen des geringen, erforderlichen Kanalquerschnitts muß der Ventilkör­per des Steuerventils auch nur einen verhältnismäßig kurzen Schalt­weg zurücklegen, so daß ein Elektromagnet als Stellantrieb für das Steuerventil völlig ausreichend ist.The control valve is also designed so that any pressure forces that occur are directed perpendicular to the movement of its valve body, so that only relatively small actuating forces are required. Because of the small, required channel cross section, the valve body of the control valve only has to travel a relatively short switching distance, so that an electromagnet as an actuator for the control valve is completely sufficient.

Gemäß einer bevorzugten Ausgestaltung der Erfindung ist beiderseits des Absperrventils, und zwar vorzugsweise in der jeweiligen Steuer­leitung zum Wechselventil hin, eine Druckmeßstelle mit einem Druckmeß­fühler oder zur Aufnahme eines solchen angeordnet;  über diese beiden Druckmeßstellen kann jeder für den Betrieb und die Betriebssicherheit relevante Druck abgenommen werden, so z.B. der Vorratsdruck im Speicher, der Förderdruck der als Pumpe arbeitenden hydraulischen Maschine und dgl. mehr. Bei geschlossenem Absperrventil muß das gemessene Druckge­fälle konstant bleiben. Ist dies nicht der Fall, dann liegt eine Stö­rung vor. Die beiden Meßstellen können mit einer Einrichtung ausge­stattet sein, welche bei einer solchen Störung Abhilfemaßnahmen er­greifen und/oder Alarm auslöst.According to a preferred embodiment of the invention, a pressure measuring point with a pressure sensor or for receiving such a valve is arranged on both sides of the shut-off valve, preferably in the respective control line to the shuttle valve; Via these two pressure measuring points, every pressure relevant for operation and operational safety can be taken off, e.g. the supply pressure in the accumulator, the delivery pressure of the hydraulic machine working as a pump and the like. More. When the shut-off valve is closed, the pressure drop measured must remain constant. If this is not the case, then there is a fault. The two measuring points can be equipped with a device which takes remedial measures in the event of such a fault and / or triggers an alarm.

Gemäß einer weiteren, bevorzugten Ausgestaltung der Erfindung ist zwischen dem Druckspeicher und dem Tank eine Absperrdrossel angeord­net, welche ggf. mit einem Stellmotor versehen sein kann. Diese Ab­sperrdrossel dient dazu, den Druck im Speicher gefahrlos zum Tank hin zu entlasten, was etwa dann erforderlich ist, wenn Reparatur- oder War­tungsarbeiten am Druckspeicher oder an der Ventilanordnung durchge­führt werden müssen. Es ist auch möglich, einen der Absperrdrossel zu­geordneten Stellmotor mit einer Überwachungseinrichtung zu verbinden, die an die beiden obengenannten Meßstellen angeschlossen ist, so daß bei Auftreten einer Störung selbsttätig der Druckspeicher entleert wird.According to a further preferred embodiment of the invention, a shut-off throttle is arranged between the pressure accumulator and the tank, which can optionally be provided with a servomotor. This shut-off throttle is used to safely relieve the pressure in the reservoir towards the tank, which is necessary, for example, when repair or maintenance work on the pressure reservoir or on the valve arrangement has to be carried out. It is also possible to connect a servomotor assigned to the shut-off throttle to a monitoring device which is connected to the two measuring points mentioned above, so that the pressure accumulator is automatically emptied when a fault occurs.

Gemäß einer weiteren Ausgestaltung der Erfindung ist mindestens ein Tëil der Ventile und Drosseln der erfindungsgemäßen Anordnung in einem gemeinsamen Block untergebracht. Bevorzugt nimmt dieser Block alle Elemente der erfindungsgemäßen Anordnung auf. Die verschiedenen Arbei­ts- und Steuerleitungen der erfindungsgemäßen Anordnung werden somit durch Bohrungen gebildet, so daß die Gefahr der Beschädigung einer Ver­bindungsleitung ausgeschlossen ist.According to a further embodiment of the invention, at least one part of the valves and throttles of the arrangement according to the invention is accommodated in a common block. This block preferably accommodates all elements of the arrangement according to the invention. The various working and control lines of the arrangement according to the invention are thus formed by bores, so that the risk of damage to a connecting line is excluded.

Dieser Block kann vorteilhafter Weise unmittelbar am Druckspeicher ange­flanscht sein; es ist aber ebensogut auch möglich, diesen Block über­all dort anzubringen, wo dies etwa aus räumlichen Gründen besonders vorteilhaft ist. Hierbei muß der Block auch nicht ohne weiteres von außen zugänglich sein, wie dies bei dem handbetätigten Absperrventil der eingangs genannten, bekannten Anordnung der Fall war.This block can advantageously be flanged directly to the pressure accumulator; however, it is equally possible to attach this block wherever this is particularly advantageous for spatial reasons. Here, the block does not have to be easily accessible from the outside, as was the case with the manually operated shut-off valve of the known arrangement mentioned at the beginning.

Im Block ist ferner vorzugsweise ein Druckbegrenzungsventil angeordnet, das den Druckspeicher mit dem Tank verbindet und den Zweck hat, im Fall des Auftretens eines unzulässigen Überdrucks im Druckspeicher diesen Überdruck bis auf einen zulässigen Wert selbsttätig zusenken. Ein solcher unzulässiger Überdruck kann beispielsweise durch mechanische Verformung des Druckspeichers oder dessen Erwärmung herbeigeführt wer­den. Es ist somit möglich, den Druckspeicher zusammen mit der erfin­dungsgemäßen Ventilanordnung in einem Fahrzeug selbst an solchen Stellen anzubringen wo er der Sonneneinstrahlung oder sonstiger Er­wärmung ausgesetzt ist. Ferner ist durch die letztgenannte Ausgestal­tung sichergestellt, daß der Druckspeicher etwa im Falle eines Unfalls nicht platzt.In the block, a pressure limiting valve is preferably also arranged, which connects the pressure accumulator to the tank and has the purpose of automatically lowering this excess pressure to a permissible value in the event of an unacceptable excess pressure in the pressure accumulator. Such an impermissible excess pressure can be brought about, for example, by mechanical deformation of the pressure accumulator or its heating. It is thus possible to mount the pressure accumulator together with the valve arrangement according to the invention in a vehicle even at locations where it is exposed to the sun's rays or other heating. Furthermore, the latter configuration ensures that the pressure accumulator does not burst in the event of an accident.

Die Erfindung schafft somit einen kompakten Absperrblock mit Sicherheits­funktionen für hydraulische Speicher mit einer Sperrstellung, einer Durchlaufstellung und der Möglichkeit zum Entleeren des Speichers un­mittelbar in den Öltank über eine Absperrdrossel. Der Steuerdruck zur Ansteuerung des eigentlichen Absperrventils, das bevorzugt als 2/2-­Wegeventil in Cartridgebauweise ausgebildet ist, wird unmittelbar den Anschlüssen für Speicher oder die angeschlossene Hydraulikeinheit ent­ nommen, wobei der jeweils höhere der beiden Drücke ausgewählt wird, um eine zuverlässige Haltewirkung zu erzielen. Ferner sind Meßan­schlüsse für die Regelung, Steuerung oder Kontrolle vorgesehen.The invention thus creates a compact shut-off block with safety functions for hydraulic accumulators with a blocking position, a continuous position and the possibility of emptying the accumulator directly into the oil tank via a blocking throttle. The control pressure for controlling the actual shut-off valve, which is preferably designed as a 2/2-way valve in a cartridge construction, is directly derived from the connections for the accumulator or the connected hydraulic unit taken, the higher of the two pressures being selected in order to achieve a reliable holding effect. Furthermore, measuring connections for regulation, control or monitoring are provided.

Sowohl das 2/2-Wegeventil in Cartridgebauweise als auch das dieses steuernde Wegesitzventil ist jeweils, wenn geschlossen, absolut dicht, so daß auch über längere Zeit hinweg irgendein Druckabfall infolge von Leckgage zuverlässig vermieden ist.Both the 2/2-way valve in cartridge design and the directional seat valve controlling this are each absolutely sealed when closed, so that any pressure drop due to leakage is reliably avoided even over a long period of time.

Zur Abstimmung der Schaltzeit sind in den Steuerleitungen Drosseln vor­gesehen.Chokes are provided in the control lines to match the switching time.

Der erfindungsemäße Absperrblock ist somit sehr kompakt und einfach aufgebaut, kann sowohl am Druckbehälter als auch an einer beliebigen Stelle etwa in einem Fahrzeug befestigt werden und es ist die Fernbe­dienung des Ventils ermöglicht, so daß sich der erfindungsgemäße Ab­sperrblock für die elektro- hydraulische Regelung der Speicherhydrau­lik eignet. Der einfach Aufbau garantiert ferner die sichere Funktion.The shut-off block according to the invention is thus very compact and simple, can be attached to the pressure vessel as well as anywhere in a vehicle, and the valve can be operated remotely, so that the shut-off block according to the invention can be used for the electro-hydraulic control of the accumulator hydraulics is suitable. The simple structure also guarantees safe operation.

Der Gegenstand der Erfindung ist anhand der beigefügten, schematischen Zeichnung beispielsweise noch näher erörtert, in deren einziger Figur schematisch ein erfindungsgemäßer Absperrblock dargestellt ist.The object of the invention is discussed in more detail with reference to the attached schematic drawing, for example, in the single figure of which a shut-off block according to the invention is shown schematically.

Der gezeigte Absperrblock 5 weist drei hydraulische Anschlüsse auf, und zwar den Anschluß P für eine entweder als Pumpe oder Arbeitsma­schine ausgebildete Hydraulikeinheit, den Anschluß S für einen Hoch­druck- oder Niederdruckspeicher und den Anschluß T für einen Tank oder Vorratsbehälter.The shut-off block 5 shown has three hydraulic connections, namely the connection P for a hydraulic unit designed either as a pump or working machine, the connection S for a high-pressure or low-pressure accumulator and the connection T for a tank or reservoir.

Im inneren des Absperrblocks 5 ist ein 2/2-Wegeventil C in Cartridge­bauweise angeordnet, das einen Steuerzylinder 6 aufweist. In diesem ist dichtend und beweglich ein Stellkolben 9 angeordnet, der an sei­ner vom Druckraum des Steuerzylinders 6 abgewandten Seite einen Ven­tilkörper 10 trägt. Dieser Ventilkörper 10 ist dazu eingerichtet, in der in der Zeichnung gezeigten Endlage gegenüber einem Ventilsitz 11 leckagefrei abzudichten.In the interior of the shut-off block 5, a 2/2-way valve C in a cartridge design is arranged, which has a control cylinder 6. In this, an actuating piston 9 is arranged in a sealing and movable manner and carries a valve body 10 on its side facing away from the pressure chamber of the control cylinder 6. This valve body 10 is set up in the end position shown in the drawing opposite a valve seat 11 seal leak-free.

Der Ventilsitz 11 unterteilt in Innenraum des Ventils C in einen er­sten Raum 7 mit einem Anschluß B angrenzend an den Stellkolben 9 und einen zweiten Raum 8 mit einem Anschluß A. Der Anschluß B ist mit einer Arbeitsleitung 3 mit dem Speicheranschluß S verbunden, während der An­schluß A über eine Arbeitsleitung 4 mit dem Anschluß P für die Hydraulik­einheit verbunden ist. Vorzugsweise ist im Ventil C eine Feder vor­gesehen, die den Stellkolben 9 und damit den Ventilkörper 10 in Anlage gegen den Ventilsitz 11 drückt.The valve seat 11 divided into the interior of the valve C into a first space 7 with a connection B adjacent to the actuating piston 9 and a second space 8 with a connection A. The connection B is connected to the storage connection S by a working line 3 during the connection A is connected via a working line 4 to the connection P for the hydraulic unit. A spring is preferably provided in valve C, which presses the actuating piston 9 and thus the valve body 10 in abutment against the valve seat 11.

Die Arbeitsleitung 4 ist über eine Steuerleitung 1 mit dem einen Ein­gang eines Wechselventiles WV verbunden, dessen anderer Eingang über eine Steuerleitung 2 mit der Arbeitsleitung 3 verbunden ist. Die bei­den Steuerleitungen 1 und 2 und damit auch die jeweilige Arbeitslei­tung 4 und 3 sind jeweils mit einem Meßanschluß M′ bzw. M˝ ausge­bildet, an dem ein Druckmeßfühler angeordnet ist.The working line 4 is connected via a control line 1 to the one input of a shuttle valve WV, the other input of which is connected to the working line 3 via a control line 2. The two control lines 1 and 2 and thus also the respective working line 4 and 3 are each formed with a measuring connection M 'or M˝, on which a pressure sensor is arranged.

Der Ausgang des Wechselventils WV ist über eine weitere Steuerleitung 10 mit dem Steuerzylinder 6 des Ventils C verbunden.The output of the shuttle valve WV is connected to the control cylinder 6 of the valve C via a further control line 10.

Das Wechselventil WV weist einen Ventilkörper auf, der jeweils jenen der beiden Eingänge des Ventils WV sperrt, der von beiden Eingängen den kleineren Druck aufweist, so daß der Steuerzylinder 6 stets mit jener Arbeitsleitung 3 oder 4 in Verbindung bringbar ist, in welcher jeweils der höhere Druck vorherrscht. Es ist somit stets dafür Vorsorge getroffen, daß, wenn der Steuerzylinder 6 mit Druckbeaufschlagt ist, dieser so hoch ist, daß der Ventilkörper 10 des Ventils C dichtend gegen den Ventilsitz 11 angedrückt bleibt.The shuttle valve WV has a valve body, which blocks that of the two inputs of the valve WV, which has the lower pressure of both inputs, so that the control cylinder 6 can always be connected to that working line 3 or 4, in each of which the higher one Pressure prevails. Provision is therefore always made that when the control cylinder 6 is pressurized, it is so high that the valve body 10 of the valve C remains pressed against the valve seat 11 in a sealing manner.

In der Steuerleitung 10 ist ein Wegesitzventil W angebracht, dessen Ruhelage in der Zeichnung gezeigt ist und das bei Betätigung eines Elektromagneten 12 gegen die Kraft einer Feder 13 aus dieser Ruhela­ge heraus bewegt wird.In the control line 10 there is a directional seat valve W, the rest position of which is shown in the drawing and which, when an electromagnet 12 is actuated, is moved out of this rest position against the force of a spring 13.

In der Ruhelage verbindet das Wegesitzventil W die beiden Zweige der Steuerleitung 10, zwischen welchen das Wegesitzventil W angeordnet ist. Gleichzeitig wird durch eine absolut dichte Ventilsitzabdich­tung eine Entlastungsleitung 11 leckagefrei abgesperrt, die das Wegesitzventil W mit dem Anschluß T für den Vorratsbehälter verbin­det.In the rest position, the directional seat valve W connects the two branches of the control line 10, between which the directional seat valve W is arranged. At the same time, a discharge line 11, which connects the directional seat valve W to the connection T for the reservoir, is blocked off leak-free by an absolutely tight valve seat seal.

Wird nun durch Ansteuern des Elektromagneten 12 das Wegesitzventil W gegen die Wirkung der Feder 13 in seine Arbeitslage versetzt, dann wird jener Zweig der Steuerleitung 10, der zum Absperrventil C hin­führt, mit der Entlastungsleitung 11 verbunden, während der andere Zweig der Steuerleitung 10 hermetisch abgedichtet wird. In diesem Fall wird der Steuerzylinder 6 über den Anschluß T entleert und somit druckfrei, so daß auf den Stellkolben 9 des Ventils C nur noch der in dessen Innenräumen 7 und 8 herrschende Druck einwirkt, diesen Stell­kolben 9 in der Zeichnung nach oben verschiebt und somit den Ventil­körper 10 vom Ventilsitz 11 abhebt, wodurch die Innenräume 7 und 8 und somit die Anschlüsse B und A des Ventils miteinander verbunden werden und zwischen den Anschlüssen S und P über die Arbeitsleitungen 3 und 4 ungehindert hydraulische Arbeitsflüssigkeit strömen kann.If the directional seat valve W is now moved into its working position against the action of the spring 13 by actuating the electromagnet 12, that branch of the control line 10 which leads to the shut-off valve C is connected to the relief line 11, while the other branch of the control line 10 is hermetically sealed becomes. In this case, the control cylinder 6 is emptied via the port T and is therefore free of pressure, so that only the pressure prevailing in the interior spaces 7 and 8 of the valve C of the valve C acts on it, displacing this control piston 9 in the drawing and thus the Valve body 10 lifts off the valve seat 11, as a result of which the interiors 7 and 8 and thus the connections B and A of the valve are connected to one another and hydraulic work fluid can flow unhindered between the connections S and P via the working lines 3 and 4.

Zwischen dem Absperrventil C und dem Wegesitzventil W ist eine er­ste Drossel DR′ vorgesehen, und zwischen diesem und dem Tankanschluß T ist in der Leitung 11 eine zweite Drossel DR ˝ vorgesehen. Diese beiden Drosseln sind dazu bestimmt, den explosionsartigen Druckab­fall im Steuerzylinder 6 des Absperrventils C zu verhindern und das gesteuerte, aber rasche öffnen des Absperrventils C mit einer vorbe­stimmten Geschwindigkeit bzw. in einer vorbestimmten Öffnungszeit zu ermöglichen.Between the shut-off valve C and the directional seat valve W, a first throttle DR 'is provided, and between this and the tank port T, a second throttle DR ˝ is provided in line 11. These two throttles are designed to prevent the explosion-like pressure drop in the control cylinder 6 of the shut-off valve C and to enable the controlled but rapid opening of the shut-off valve C at a predetermined speed or in a predetermined opening time.

Die bisher beschriebenen Merkmale sind für die Funktion des erfindungs­gemäßen Absperrblockes voll ausreichend, wobei ggf. sogar auf die Druckmeßanschlüsse M′ und M˝ verzichtet werden kann. Bevorzugt weist der Absperrblock aber noch ein Druckbegrenzungsventil DB auf, welches die Arbeitsleitung 3 mit der Entlastungsleitung 11 und somit die Anschlüsse S und T miteinander verbindet. Dieses Druckbegrenzungs­ventil DB entlastet eventuelle Druckerhöhungen durch äußere Einflüsse (z.B. Temperatur, Verformung usw.), wie sie besonders im Fäll eines Unfalls auftreten können. Soweit der Anstieg des Druckes im Druck­speicher durch äußere Einwirkung nicht einen kritischen Wert annehmen kann, kann das Ventil DB entfallen.The features described so far are fully sufficient for the function of the shut-off block according to the invention, it possibly even being possible to dispense with the pressure measuring connections M 'and M˝. However, the shut-off block preferably also has a pressure relief valve DB, which the working line 3 with the relief line 11 and thus the connections S and T with each other. This pressure relief valve DB relieves any pressure increases caused by external influences (e.g. temperature, deformation, etc.), which can occur particularly in the event of an accident. If the increase in pressure in the pressure accumulator cannot take on a critical value due to external influences, the valve DB can be omitted.

Parallel zu diesem Ventil DB ist eine Absperrdrossel D angeordnet, durch deren öffnen ebenfalls die Arbeitsleitung 3 mit der Ablaßlei­tung 11 und somit der Anschluß S für den Druckspeicher mit dem Anschluß T für den Vorratsbehälter verbunden werden kann. Es ist somit möglich, durch Öffnen der Absperrdrossel D den Druckspeicher abzulassen und druckfrei zu machen. Dies ist beispielsweise dann erforderlich, wenn Reparaturen oder ein Wechsel des Hydrauliköles vorgenommen werden müssen.In parallel to this valve DB, a shut-off throttle D is arranged, through the opening of which the working line 3 can also be connected to the discharge line 11 and thus the connection S for the pressure accumulator to the connection T for the storage container. It is thus possible to lower the pressure accumulator by opening the shut-off throttle D and to make it pressure-free. This is necessary, for example, if repairs or a change in the hydraulic oil have to be carried out.

Die Absperrdrossel D kann fernbedienbar sein und mit einer Überwachungs­einrichtung oder einem Fühler gekoppelt sein. So ist es beispiels­weise möglich, die Absperrdrossel D etwa mit einem die Anordnung ver­schließenden Deckel so zu koppeln, daß bei Abnahme dieses Deckels sicherheitshalber der Druckspeicher entleert wird. Es ist auch möglich, die Absperrdrossel D mit einer leicht zugänglichen Handhabe zu versehen, über welche z.B. nach einem Unfall der Druckspeicher abgelassen werden kann.The shut-off throttle D can be operated remotely and can be coupled to a monitoring device or a sensor. For example, it is possible to couple the shut-off throttle D with a cover closing the arrangement in such a way that when the cover is removed, the pressure accumulator is emptied for safety reasons. It is also possible to provide the shut-off throttle D with an easily accessible handle, via which e.g. the pressure accumulator can be released after an accident.

Der gezeigte Sicherheits- oder Absperrblock weist die folgenden Funk­tionen auf:

  • 1. In der in der Zeichnung gezeigten Ruhelage ist das Absperrventil C geschlossen.
  • 2. Wenn W angesteuert wird, dann öffnet C.
  • 3. Eventuelle Druckerhöhungen durch äußere Einflüsse werden über DB entlastet.
  • 4. Durch Öffnen von D kann der Druckspeicher in den Tank entleert wer­den.
  • 5. Das Cartridge-Element C wird mit dem jeweils höheren Druck der Anschlüsse A oder B beaufschlagt.
The safety or shut-off block shown has the following functions:
  • 1. In the rest position shown in the drawing, the shut-off valve C is closed.
  • 2. When W is activated, C. opens
  • 3. Any pressure increases due to external influences are relieved via DB.
  • 4. By opening D the pressure accumulator can be emptied into the tank.
  • 5. The cartridge element C is pressurized with the higher pressure at ports A or B.

Claims (9)

1. Ventilanordnung zum Anschluß eines hydraulischen Druckspeichers an eine hydraulische Pumpe bzw. hydraulische Arbeitsmaschine, mit den folgenden Merkmalen:
- Ein leckagefreies Absperrventil mit einem Anschluß für den Druck­speicher und einem Anschluß für die Pumpe bzw. Arbeitsmaschine, und
- vorzugsweise einem bei Erreichen eines zuläßigen Höchstdruckes öffnenden Sicherheitsventil, das an den Druckspeicher sowie einem Tank angeschlossen ist,
dadurch gekennzeichnet,
- daß das Absperrventil (C) einen mit einem Steuerdruck beaufschlag­baren, in einem Steuerzylinder (6) leckagefrei beweglichen Stell­kolben (9) aufweist, der einen bei Druckbeaufschlagung leckagefrei dichtend gegen einen Ventilsitz (11) andrückbaren Ventilkörper (10) trägt,
- daß ein Wechselventil (WV) über jeweils eine Steuerleitung (1, 2) an jeden der beiden Anschlüsse (A, B) des Absperrventils (C) so­wie an eine Zuleitung (10) zum Steuerzylinder (6) so angeschlossen ist, daß diese Zuleitung (10) jeweils mit jenem der beiden An­schlüsse (1, 2) verbunden ist, in dem der höhere Druck herrscht, und
- daß in der Zuleitung (10) zum Steuerzylinder (6) ein fernbetätig­bares (Elektromagnet 12), leckagefreies Steuerventil (W) ange­ordnet ist, das in seiner Arbeitslage die Verbindung zwischen dem Wechselventil (WV) und dem Steuerzylinder (6) trennt und diesen zum Tank (Anschluß T) hin entlastet.1. Valve arrangement for connecting a hydraulic pressure accumulator to a hydraulic pump or hydraulic machine, with the following features:
- A leak-free shut-off valve with a connection for the pressure accumulator and a connection for the pump or machine, and
preferably a safety valve which opens when a permissible maximum pressure is reached and which is connected to the pressure accumulator and to a tank,
characterized,
- That the shut-off valve (C) has an actuating piston (9) which can be acted upon with a control pressure, is leak-free movable in a control cylinder (6) and which carries a valve body (10) which can be pressed against a valve seat (11) in a leak-tight manner when pressurized,
- That a shuttle valve (WV) via a control line (1, 2) to each of the two connections (A, B) of the shut-off valve (C) and to a supply line (10) to the control cylinder (6) is connected so that this supply line (10) is connected to that of the two connections (1, 2) in which the higher pressure prevails, and
- That in the supply line (10) to the control cylinder (6) a remotely operable (electromagnet 12), leakage-free control valve (W) is arranged, which in its working position separates the connection between the shuttle valve (WV) and the control cylinder (6) and this to Relieved tank (port T). 2. Ventilanordnung nach Anspruch 1, dadurch gekennzeichnet, daß in der Zuleitung (10) zwischen dem Steuerventil (WV) und dem Steuer­zylinder (6) eine Drossel (DR′) angeordnet ist.2. Valve arrangement according to claim 1, characterized in that a throttle (DR ') is arranged in the feed line (10) between the control valve (WV) and the control cylinder (6). 3. Ventilanordnung nach einem der Ansprüche 1 oder 2, dadurch ge­kennzeichnet, daß zwischen dem Steuerventil (WV) und dem Tank (Anschluß T) eine zweite Drossel (DR˝) angeordnet ist.3. Valve arrangement according to one of claims 1 or 2, characterized in that a second throttle (DRV) is arranged between the control valve (WV) and the tank (connection T). 4. Ventilanordnung nach einem der Ansprüche 1 bis 3, dadurch gekenn­zeichnet, daß das Absperrventil (C) als 2/2-Wegeventil in Cartridge-­Ausführung ausgebildet ist.4. Valve arrangement according to one of claims 1 to 3, characterized in that the shut-off valve (C) is designed as a 2/2-way valve in a cartridge design. 5. Ventilanordnung nach einem der Ansprüche 1 bis 4, dadurch gekenn­zeichnet, daß das Steuerventil (WV) als Wegesitzventil mit elektro­magnetischem Antrieb (12) ausgebildet ist.5. Valve arrangement according to one of claims 1 to 4, characterized in that the control valve (WV) is designed as a directional seat valve with an electromagnetic drive (12). 6. Ventilanordnung nach einem der Ansprüche 1 bis 5, dadurch gekenn­zeichnet, daß an den beiden Anschlüssen (A, B) des Absperrventils (C) jeweils eine Druckmeßstelle (M′, M˝) für einen Druck-Signal­geber angeordnet ist.6. Valve arrangement according to one of claims 1 to 5, characterized in that at each of the two connections (A, B) of the shut-off valve (C) a pressure measuring point (M ', M˝) is arranged for a pressure signal transmitter. 7. Ventilanordnung nach einem der Ansprüche 1 bis 6, dadurch gekenn­zeichnet, daß zwischen dem Anschluß (S) für den Druckspeicher und jenem (C) für den Tank eine Absperrdrossel (D) angeordnet ist.7. Valve arrangement according to one of claims 1 to 6, characterized in that a shut-off throttle (D) is arranged between the connection (S) for the pressure accumulator and that (C) for the tank. 8. Ventilanordnung nach einem der Ansprüche 1 bis 7, dadurch gekenn­zeichnet, daß mindestens ein Teil der Ventile (C, WV) und ggf. Drosseln (D, DR′, DR˝) in einem gemeinsamen Block (5) angebracht sind.8. Valve arrangement according to one of claims 1 to 7, characterized in that at least some of the valves (C, WV) and possibly throttles (D, DR ', DR˝) are mounted in a common block (5). 9. Ventilanordnung nach Anspruch 8, dadurch gekennzeichnet, daß im Block (5) das als Druckbegrenzungsventil (DB) ausgebildete Sicher­heitsventil angeordnet ist.9. Valve arrangement according to claim 8, characterized in that the safety valve designed as a pressure relief valve (DB) is arranged in the block (5).
EP86114822A 1986-01-27 1986-10-24 Valve arrangement for hydraulic accumulator Expired - Lifetime EP0230529B1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT86114822T ATE72693T1 (en) 1986-01-27 1986-10-24 VALVE ASSEMBLY FOR A HYDRAULIC ACCUMULATOR.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE19863602362 DE3602362A1 (en) 1986-01-27 1986-01-27 VALVE ARRANGEMENT FOR A HYDRAULIC PRESSURE STORAGE
DE3602362 1986-01-27

Publications (3)

Publication Number Publication Date
EP0230529A2 true EP0230529A2 (en) 1987-08-05
EP0230529A3 EP0230529A3 (en) 1989-04-26
EP0230529B1 EP0230529B1 (en) 1992-02-19

Family

ID=6292702

Family Applications (1)

Application Number Title Priority Date Filing Date
EP86114822A Expired - Lifetime EP0230529B1 (en) 1986-01-27 1986-10-24 Valve arrangement for hydraulic accumulator

Country Status (5)

Country Link
US (1) US4706930A (en)
EP (1) EP0230529B1 (en)
AT (1) ATE72693T1 (en)
DE (2) DE3602362A1 (en)
DK (1) DK166551B1 (en)

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DE4223389A1 (en) * 1992-07-16 1994-01-20 Rexroth Mannesmann Gmbh Control arrangement for at least one hydraulic consumer
DE4438899C1 (en) * 1994-10-31 1995-09-07 Hydac Technology Gmbh Energy recovery installation for work tool
US5477677A (en) * 1991-12-04 1995-12-26 Hydac Technology Gmbh Energy recovery device
DE19638837A1 (en) * 1996-09-21 1998-03-26 Wabco Gmbh Two-unit pressure control system
EP2603705A1 (en) * 2010-08-09 2013-06-19 Parker Hannifin Manufacturing Sweden AB Hydraulic control system

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US5375619A (en) * 1993-04-28 1994-12-27 Foster; Raymond K. Protective circuit for pressure and return
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US6427967B1 (en) * 1997-07-15 2002-08-06 Rowland Frank Evans Valve, unit, assembly and system
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US8597849B2 (en) * 2005-08-30 2013-12-03 GM Global Technology Operations LLC Pressure activated shut-off valve
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CN108502083A (en) * 2018-04-20 2018-09-07 重庆大学 A kind of energy-storage hydraulic bicycle being suitble to more hillside fields shapes
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US5477677A (en) * 1991-12-04 1995-12-26 Hydac Technology Gmbh Energy recovery device
DE4223389A1 (en) * 1992-07-16 1994-01-20 Rexroth Mannesmann Gmbh Control arrangement for at least one hydraulic consumer
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DE4438899C1 (en) * 1994-10-31 1995-09-07 Hydac Technology Gmbh Energy recovery installation for work tool
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EP2603705A1 (en) * 2010-08-09 2013-06-19 Parker Hannifin Manufacturing Sweden AB Hydraulic control system
EP2603705A4 (en) * 2010-08-09 2017-04-05 Parker Hannifin Manufacturing Sweden AB Hydraulic control system

Also Published As

Publication number Publication date
DK578386A (en) 1987-07-28
DK578386D0 (en) 1986-12-02
EP0230529A3 (en) 1989-04-26
DK166551B1 (en) 1993-06-07
ATE72693T1 (en) 1992-03-15
EP0230529B1 (en) 1992-02-19
DE3602362A1 (en) 1987-07-30
DE3683933D1 (en) 1992-03-26
US4706930A (en) 1987-11-17

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