EP0389787B1 - Multiple way valve - Google Patents

Multiple way valve Download PDF

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Publication number
EP0389787B1
EP0389787B1 EP90103290A EP90103290A EP0389787B1 EP 0389787 B1 EP0389787 B1 EP 0389787B1 EP 90103290 A EP90103290 A EP 90103290A EP 90103290 A EP90103290 A EP 90103290A EP 0389787 B1 EP0389787 B1 EP 0389787B1
Authority
EP
European Patent Office
Prior art keywords
piston
control
pressure
control chamber
valve
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.)
Expired - Lifetime
Application number
EP90103290A
Other languages
German (de)
French (fr)
Other versions
EP0389787A3 (en
EP0389787A2 (en
Inventor
Günter Dipl.-Ing. Hilmer
Walter Kolb
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.)
CNH Industrial Baumaschinen GmbH
Original Assignee
O&K Orenstein and Koppel GmbH
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Publication date
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Publication of EP0389787A2 publication Critical patent/EP0389787A2/en
Publication of EP0389787A3 publication Critical patent/EP0389787A3/en
Application granted granted Critical
Publication of EP0389787B1 publication Critical patent/EP0389787B1/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
    • 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
    • F15B13/0401—Valve members; Fluid interconnections therefor
    • F15B13/0402—Valve members; Fluid interconnections therefor for linearly sliding valves, e.g. spool valves
    • 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
    • Y10T137/86493—Multi-way valve unit
    • Y10T137/86574—Supply and exhaust
    • Y10T137/86582—Pilot-actuated
    • 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
    • Y10T137/86493—Multi-way valve unit
    • Y10T137/86574—Supply and exhaust
    • Y10T137/86622—Motor-operated
    • Y10T137/8663—Fluid motor

Definitions

  • the invention relates to a multi-way valve according to the preamble of claim 1.
  • a valve is arranged in the counter-holding piston, which is opened by the valve slide when it is moved into a position corresponding to a floating position of the consumer by appropriate application of maximum control pressure.
  • a likewise known multi-way valve was improved, in which pressure relief in the control chamber of the counter-holding piston was brought about by a switchable three-way valve located outside the multi-way valve.
  • Such valves are basically complex and prone to failure.
  • the invention is therefore based on the object of simplifying a multi-way valve of the generic type and making it less prone to failure.
  • the essence of the invention lies in the fact that a corresponding dimensioning of the surface of the part of the valve spool designed as a piston, which can be acted upon by the control valve for the floating position, on the one hand, and of the counter-holding piston, on the other hand, permits displacement of the counter-holding piston against the maximum control pressure located in its control chamber.
  • the counter-holding piston no longer has a valve, but is completely closed over its entire cross-section.
  • control chamber is no longer relieved of pressure; rather, the pressure relief valve of the entire control pressure system, which is present anyway, is used to discharge the control liquid which is displaced from the control chamber when the counter-holding piston is displaced from the holding position into its evasive position while maintaining the maximum control pressure.
  • One or more hydraulically actuated piston-cylinder drives 1 each have a cylinder 2 and a piston 3 which is guided in a longitudinally displaceable manner therein.
  • the piston rod 4 passes through a piston ring space 5 formed between the piston 3 and the assigned end of the cylinder 2.
  • a piston chamber 6 is formed between the piston 3 and the assigned end of the cylinder 2, the cross section of the piston chamber 6 the cross-section of the piston rod 4 is larger than the cross-section of the piston annulus 5.
  • the respective piston annulus 5 on the one hand and the respective piston chamber 6 on the other are each connectable via a pressure medium line 7 or 8 to a pump 9 or a tank 10 serving as a working pressure medium source which in turn the pump 9 is also connected.
  • the actuation of the drives 1 takes place via a multi-way valve 11, which is partly only shown schematically.
  • This multi-way valve 11 has a piston 12 serving as a valve slide, the central portion of which serves to actuate a valve block 13 which serves to control the pressure medium paths between Drive 1 and pump 9 or tank 10 is used.
  • the two pressure medium lines 7, 8 open into the valve block 13 in a conventional manner.
  • a return line 14 leads to the tank 10 and a pressure medium supply line 15 leads from the pump 9 to the valve block 13.
  • In the drawing is a middle position of the piston 12 and thus the corresponding valve slide, in which the pressure medium lines 7 and 8 are shut off, ie the piston rods 4 of the drives 1 are hydraulically locked to their two possible displacement directions.
  • the pressure medium line 8 is connected to the pump 9 and the pressure medium line 7 to the tank 10, so that the respective piston chamber 6 is pressurized , which leads to an extension of the piston 3 with the piston rod 4 from the cylinder 2. In this way, the load carried by the drive 1 is lifted. If, on the other hand, the piston 12 is shifted from the center position shown in the drawing to the right into a second working position, then the pressure medium line 7 and thus the respective piston annulus 5 is pressurized, while the respective piston chamber 6 via line 8 to the Tank 10 connected, so it is relieved. This leads to the piston rod 4 being retracted into the cylinder 2, that is to say to a lowering of the load formed, for example, by a leveling blade.
  • the piston 12 ends with its one end 16, which is on the left in the drawing, in a first control chamber 17. With its other end 18 it opens into a second one Control room 19.
  • the control rooms 17, 19 are formed overall in the housing 20 of the valve 11, which is generally made of several parts.
  • a receiving section 21 which is tapered relative to the piston 12 and which is formed in one piece with the piston 12 and extends coaxially with its central longitudinal axis 22.
  • Two spring support plates 23, 24 are arranged on the receiving section 21.
  • One of the support plates 23 facing the piston 12 lies in the illustrated central position of the piston 12 with an inner ring section 25 against the piston 12 and with an outer flange ring 26 against a stop 27 fixed to the housing, which is formed by a wall delimiting the second control chamber 19.
  • the other spring support plate 24 lies with an inner ring portion 25 'against a locking ring 28 on the section 21.
  • the support plate 24 is supported on its side facing away from the piston 12 against an annular rim 29 of a counter-holding piston 30. Between the two support plates 23, 24 there are two prestressed helical compression springs 31, 32.
  • the left support plate 23 is supported with its flange ring 26 against the stop fixed to the housing 27, remains in its starting position.
  • the other support plate 24 is carried by the locking ring 28, so that the two compression springs 31, 32 are further compressed. If the piston 12 is shifted to the right in the drawing, the support plate 24 is supported against the ring rim 29 of the counter-holding piston 30, is thus also held in place while the support plate 23 is carried by the piston 12. In this case, too, the two compression springs 31, 32 are compressed further, ie they exert a force on the piston 12 which counteracts the displacement movement of the piston 12.
  • the described actuations of the piston 12 serving as a valve slide take place by appropriately applying control pressure to the first control chamber 17 and the second control chamber 19, the other control chamber 19 and 17 being relieved of pressure.
  • the first control chamber 17 is connected via a control line 33 to a manually operated pilot valve 34, which in turn is connected to a pump 35 serving as a control pressure medium source via a supply line 36.
  • the second control chamber 19 is connected via a control line 37 to a basically similarly designed, likewise manually operated pilot valve 38, which is also connected to the supply line 36.
  • Both pilot valves 34, 38 are connected to the tank 10 via a return line 39.
  • Both pilot valves 34, 38 can of course be combined in a conventional manner to form a valve, in which case only one actuating lever 40 would then have to be provided, which for pressurizing the first control chamber 17 from its central position in one direction and for pressurizing the second control chamber 19 in the other Direction would be pivoted.
  • the counter-holding piston 30 is guided in its central cylindrical section 41 in a sealed manner by means of a seal 42 in a cylinder guide 43 coaxial with the axis 22.
  • a seal 42 in a cylinder guide 43 coaxial with the axis 22.
  • This side of the counter-holding piston 30 is located in a control chamber 46 which is constantly acted upon by the supply line 36 with the full, ie maximum, control pressure from the pump 35.
  • the control chamber 46 is closed by means of a locking screw 47 against which a biasing spring 48 designed as a helical compression spring is supported, which is supported against the counter-holding piston 30 and presses it in the direction of the piston 12, that is to say it presses the annular collar 44 against the stop 45.
  • the control chamber 46 is also connected to the tank 10 via a return line 49, in which there is a pressure relief valve 50.
  • the diameter D1 of the cylindrical piston 12 is larger than the diameter D2 of the cylindrical section 41 of the counter-holding piston 30.
  • the pilot valves 34, 38 are designed as continuously working pressure reducing valves, so that the control spaces 17, 19 alternately and in each case can be acted upon with different control pressure, which is smaller than the maximum control pressure supplied by the pump 35 in the control chamber 46 for the described loading of the respective piston annulus 5 for lowering the load or for loading the respective piston chamber 6 for lifting the load effective area of the piston 12 with the diameter D1 located in the control chamber 17 is larger than the effective area of the counter-holding piston 30 corresponding to the diameter D2, this remains in its holding position shown in the drawing.
  • the pilot valve 34 is actuated, whereby the first control chamber 17 is acted upon with control liquid, the pressure of which corresponds to the degree of actuation of the actuating lever 40, the pressure of which is therefore only a partial pressure corresponds to the maximum control pressure.
  • the piston 12 is displaced in the direction of the second control chamber 19, the spring support plate 23 being carried along, while the other spring support plate 24 remains in its position against the ring rim 29 of the counter-holding piston 30.
  • the pilot valve 38 is opened accordingly, so that control fluid 19 reaches the second control chamber.
  • This also acts on the piston 12 via a surface corresponding to the diameter D1 and displaces it in the direction of the first control chamber 17, the spring support plate 23 remaining in its position on the stop 27.
  • the other support plate 24 is carried on the locking ring 28, which in turn compresses the two compression springs 31, 32.
  • the shifting movement continues until the already mentioned balance of forces is established. Since the pressure in the control chamber 46 is greater than in the second control chamber 19, the counter-holding piston 30 remains in its holding position.
  • the pilot valves 34, 38 are each connected in their non-actuated position via the return line 39 to the tank 10, so that when the piston 12 shifts, the control liquid 17 or 19 displaced in the non-pressurized control chamber 17 or 19 can flow out.
  • the piston 12 serving as a valve slide must be moved to an extreme position for the corresponding actuation of the valve block 13.
  • This extreme position corresponds to a position shifted further to the right.
  • the full control pressure supplied by the pump 35 is applied to the first control chamber 17 by completely opening the control valve 34. Since in this the force acting on the piston 12 in the direction of the counter-holding piston 30 is greater than the force acting on the latter in the opposite direction from the control chamber 46, the piston 12 is displaced until the receiving section 21 against the facing bottom 51 of the Counter piston 30 abuts.
  • the piston 12 then presses the counter-holding piston 30 in the direction of the control chamber 46 into an evasive position.
  • the control liquid located here under the full, that is to say maximum control pressure is pressed into the tank 10 via the pressure limiting valve 50.
  • the counter-holding piston 30 can thus partially participate in the movement of the piston 12.
  • the maximum possible stroke H1 of the piston 12 relative to the counter-holding piston 30 is predetermined by the distance between the receiving section 21 and the base 51 of the counter-holding piston 30.
  • the piston 12 can be maximally displaced by this stroke H1 if the "lowering the load” function is activated.
  • the piston 12 can then be moved by the stroke H2 are determined by the distance between the counter-holding piston 30 and the locking screw 47.
  • This second stroke H2 can then be controlled for the "floating position" function. It corresponds to the stroke of the counter-holding piston 30 from the holding position into the evasive position.
  • the pressure limiting valve 50 also has the main function of keeping the control pressure supplied by the pump 35 constant. If it is exceeded, the pressure relief valve 50 opens and the pressure to the tank 10 can be reduced.
  • the maximum control pressure is not only constantly present in the control chamber 46, but also in the supply line 36 upstream of the pilot valves 34, 38.

Description

Die Erfindung betrifft ein Mehrwege-Ventil nach dem Oberbegriff des Anspruches 1.The invention relates to a multi-way valve according to the preamble of claim 1.

Bei einem derartigen aus der DE-C- 3508 340 bekannten Mehrwege-Ventil ist im Gegenhaltekolben ein Ventil angeordnet, das vom Ventilschieber geöffnet wird, wenn dieser durch entsprechende Beaufschlagung mit maximalem Steuerdruck in eine einer Schwimmstellung des Verbrauchers entsprechende Stellung bewegt wird. Damit wurde ein ebenfalls bekanntes Mehrwege-Ventil verbessert, bei dem eine Druckentlastung in der Steuerkammer des Gegenhaltekolbens durch ein außerhalb des Mehrwege-Ventils befindliches umschaltbares Dreiwege-Ventil bewirkt wurde. Solche Ventile sind grundsätzlich aber aufwendig und störanfällig.In such a multi-way valve known from DE-C-3508 340, a valve is arranged in the counter-holding piston, which is opened by the valve slide when it is moved into a position corresponding to a floating position of the consumer by appropriate application of maximum control pressure. Thus, a likewise known multi-way valve was improved, in which pressure relief in the control chamber of the counter-holding piston was brought about by a switchable three-way valve located outside the multi-way valve. Such valves are basically complex and prone to failure.

Der Erfindung liegt daher die Aufgabe zugrunde, ein Mehrwege-Ventil der gattungsgemäßen Art zu vereinfachen und weniger störanfällig zu machen.The invention is therefore based on the object of simplifying a multi-way valve of the generic type and making it less prone to failure.

Diese Aufgabe wird erfindungsgemäß durch die Merkmale im Kennzeichnungsteil des Anspruches 1 gelöst. Der Kern der Erfindung liegt darin, daß durch eine entsprechende Bemaßung der Fläche des für die Schwimmstellung mit Steuerdruck beaufschlagbaren Teils des als Kolben ausgebildeten Ventilschiebers einerseits und des Gegenhaltekolbens andererseits eine Verschiebung des Gegenhaltekolbens gegen den in seiner Steuerkammer befindlichen maximalen Steuerdruck möglich wird. Der Gegenhaltekolben weist also kein Ventil mehr auf, sondern ist vollkommen über seinen gesamten Querschnitt geschlossen ausgebildet. Eine Druckentlastung in der Steuerkammer erfolgt nicht mehr; vielmehr wird das ohnehin vorhandene Druckbegrenzungsventil des gesamten Steuerdruck-Systems dazu verwendet, um die bei einem Verschieben des Gegenhaltekolbens aus der Haltestellung in seine Ausweichstellung aus der Steuerkammer verdrängte Steuerflüssigkeit bei Aufrechterhaltung des maximalen Steuerdrucks abzuführen.This object is achieved by the features in the characterizing part of claim 1. The essence of the invention lies in the fact that a corresponding dimensioning of the surface of the part of the valve spool designed as a piston, which can be acted upon by the control valve for the floating position, on the one hand, and of the counter-holding piston, on the other hand, permits displacement of the counter-holding piston against the maximum control pressure located in its control chamber. The counter-holding piston no longer has a valve, but is completely closed over its entire cross-section. The control chamber is no longer relieved of pressure; rather, the pressure relief valve of the entire control pressure system, which is present anyway, is used to discharge the control liquid which is displaced from the control chamber when the counter-holding piston is displaced from the holding position into its evasive position while maintaining the maximum control pressure.

Weitere Merkmale, Einzelheiten und Vorteile der Erfindung ergeben sich aus der nachfolgenden Beschreibung eines Ausführungsbeispiels anhand der Zeichnung, die die erfindungswesentlichen Teile in konstruktiver Darstellung und alle anderen für die Erfindung selber nicht wesentlichen, zur Erläuterung aber zweckmäßigen Teile in schematischer Darstellung zeigt.Further features, details and advantages of the invention will become apparent from the following description of an embodiment with reference to the drawing, which shows the parts essential to the invention in a constructive representation and all other parts which are not essential for the invention itself, but are useful for explanation Parts in a schematic representation shows.

Ein oder mehrere hydraulisch beaufschlagte Kolben-Zylinder-Antriebe 1 weisen jeweils einen Zylinder 2 und einen in diesem längsverschiebbar geführten Kolben 3 auf. Am Kolben 3 ist jeweils eine abgedichtet aus einem Ende des Zylinders 2 herausgeführte Kolbenstange 4 angebracht. Mittels des oder der Antriebe 1 wird beispielsweise eine Planierschar eines Graders oder die Schaufel eines Radladers oder dergleichen in der Höhe verstellt. Die Kolbenstange 4 durchsetzt einen zwischen dem Kolben 3 und dem zugeordneten Ende des Zylinders 2 ausgebildeten Kolbenringraum 5. Auf der der Kolbenstange 4 abgewandten Seite ist zwischen dem Kolben 3 und dem zugeordneten Ende des Zylinders 2 ein Kolbenraum 6 ausgebildet, wobei der Querschnitt des Kolbenraums 6 um den Querschnitt der Kolbentange 4 größer ist als der Querschnitt des Kolbenringraums 5. Der jeweilige Kolbenringraum 5 einerseits und der jeweilige Kolbenraum 6 andererseits sind jeweils über eine DruckmittelLeitung 7 bzw. 8 mit einer als Arbeitsdruckmittelquelle dienenden Pumpe 9 bzw. einem Tank 10 verbindbar, an den wiederum die Pumpe 9 auch angeschlossen ist.One or more hydraulically actuated piston-cylinder drives 1 each have a cylinder 2 and a piston 3 which is guided in a longitudinally displaceable manner therein. A piston rod 4, which is sealed out from one end of the cylinder 2, is attached to the piston 3. By means of the drive or drives 1, for example, a leveler of a grader or the bucket of a wheel loader or the like is adjusted in height. The piston rod 4 passes through a piston ring space 5 formed between the piston 3 and the assigned end of the cylinder 2. On the side facing away from the piston rod 4, a piston chamber 6 is formed between the piston 3 and the assigned end of the cylinder 2, the cross section of the piston chamber 6 the cross-section of the piston rod 4 is larger than the cross-section of the piston annulus 5. The respective piston annulus 5 on the one hand and the respective piston chamber 6 on the other are each connectable via a pressure medium line 7 or 8 to a pump 9 or a tank 10 serving as a working pressure medium source which in turn the pump 9 is also connected.

Die Ansteuerung der Antriebe 1 erfolgt über ein Mehrwege-Ventil 11, das teilweise nur schematisch dargestellt ist. Dieses Mehrwege-Ventil 11 weist einen als Ventilschieber dienenden Kolben 12 auf, dessen mittlerer Abschnitt zur Betätigung eines Ventilblocks 13 dient, der zur Steuerung der Druckmittelwege zwischen Antrieb 1 und Pumpe 9 bzw. Tank 10 dient. Hierzu münden in üblicher Weise die beiden Druckmittel-Leitungen 7, 8 in den Ventilblock 13. Weiterhin führt eine Rücklauf-Leitung 14 zum Tank 10 und eine Druckmittel-Versorgungs-Leitung 15 von der Pumpe 9 zum Ventilblock 13. In der Zeichnung ist eine Mittelstellung des Kolbens 12 und damit des entsprechenden Ventilschiebers dargestellt, in der die Druckmittel-Leitungen 7 und 8 abgesperrt sind, d.h. die Kolbenstangen 4 der Antriebe 1 sind ihren beiden möglichen Verschieberichtungen hydraulisch verriegelt. Wenn der Kolben 12 in der Zeichnung nach links in eine 1. Arbeitsstellung verschoben wird, dann wird die Druckmittel-Leitung 8 an die Pumpe 9 und die Druckmittel-Leitung 7 an den Tank 10 angeschlossen, so daß der jeweilige Kolbenraum 6 mit Druckmittel beaufschlagt wird, was zu einem Ausfahren des Kolbens 3 mit Kolbenstange 4 aus dem Zylinder 2 führt. Auf diese Weise wird die vom Antrieb 1 getragene Last gehoben. Wenn dagegen der Kolben 12 aus der dargestellten Mittellage in der Zeichnung nach rechts in eine 2. Arbeitsstellung verschoben wird, dann wird die Druckmittel-Leitung 7 und damit der jeweilige Kolbenringraum 5 mit Druckmittel beaufschlagt, während der jeweilige Kolbenraum 6 über die Leitung 8 an den Tank 10 angeschlossen, also entlastet wird. Dies führt zu einem Einfahren der Kolbenstange 4 in den Zylinder 2, also zu einem Absenken der beispielsweise durch eine Planierschaufel gebildeten Last.The actuation of the drives 1 takes place via a multi-way valve 11, which is partly only shown schematically. This multi-way valve 11 has a piston 12 serving as a valve slide, the central portion of which serves to actuate a valve block 13 which serves to control the pressure medium paths between Drive 1 and pump 9 or tank 10 is used. For this purpose, the two pressure medium lines 7, 8 open into the valve block 13 in a conventional manner. Furthermore, a return line 14 leads to the tank 10 and a pressure medium supply line 15 leads from the pump 9 to the valve block 13. In the drawing is a middle position of the piston 12 and thus the corresponding valve slide, in which the pressure medium lines 7 and 8 are shut off, ie the piston rods 4 of the drives 1 are hydraulically locked to their two possible displacement directions. If the piston 12 is moved to the left in the drawing in a 1st working position, then the pressure medium line 8 is connected to the pump 9 and the pressure medium line 7 to the tank 10, so that the respective piston chamber 6 is pressurized , which leads to an extension of the piston 3 with the piston rod 4 from the cylinder 2. In this way, the load carried by the drive 1 is lifted. If, on the other hand, the piston 12 is shifted from the center position shown in the drawing to the right into a second working position, then the pressure medium line 7 and thus the respective piston annulus 5 is pressurized, while the respective piston chamber 6 via line 8 to the Tank 10 connected, so it is relieved. This leads to the piston rod 4 being retracted into the cylinder 2, that is to say to a lowering of the load formed, for example, by a leveling blade.

Der Kolben 12 endet mit seinem einen - in der Zeichnung linken - Ende 16 in einem ersten Steuerraum 17. Mit seinem anderen Ende 18 mündet er in einen zweiten Steuerraum 19. Die Steuerräume 17,19 sind insgesamt im in der Regel mehrteilig ausgebildeten Gehäuse 20 des Ventils 11 ausgebildet. An das Ende 18 des Kolbens 12 schließt sich ein gegenüber dem Kolben 12 verjüngter Aufnahme-Abschnitt 21 an, der einstückig mit dem Kolben 12 ausgebildet ist und koaxial zu dessen Mittel-Längs-Achse 22 verläuft.The piston 12 ends with its one end 16, which is on the left in the drawing, in a first control chamber 17. With its other end 18 it opens into a second one Control room 19. The control rooms 17, 19 are formed overall in the housing 20 of the valve 11, which is generally made of several parts. At the end 18 of the piston 12 there is a receiving section 21 which is tapered relative to the piston 12 and which is formed in one piece with the piston 12 and extends coaxially with its central longitudinal axis 22.

Auf dem Aufnahme-Abschnitt 21 sind zwei Feder-Stützteller 23, 24 angeordnet. Der eine dem Kolben 12 zugewandte Stützteller 23 liegt in der dargestellten Mittelstellung des Kolbens 12 mit einem inneren Ringabschnitt 25 gegen den Kolben 12 und mit einem äußeren Flanschring 26 gegen einen gehäusefesten Anschlag 27 an, der durch eine den zweiten Steuerraum 19 begrenzende Wand gebildet wird. Der andere Feder-Stützteller 24 liegt mit einem inneren Ringabschnitt 25′ gegen einen Sicherungsring 28 auf dem Abschnitt 21 an. Weiterhin stützt sich der Stützteller 24 auf seiner dem Kolben 12 abgewandten Seite gegen einen Ringrand 29 eines Gegenhaltekolbens 30 ab. Zwischen den beiden Stütztellern 23, 24 befinden sich zwei vorgespannte Schrauben-Druckfedern 31, 32. Wenn der Kolben 12 in der bereits angesprochenen Weise in der Zeichnung nach links verschoben wird, dann stützt sich der linke Stützteller 23 mit seinem Flanschring 26 gegen den gehäusefesten Anschlag 27 ab, verbleibt also in seiner Ausgangslage. Der andere Stützteller 24 wird vom Sicherungsring 28 mitgenommen, so daß beide Druckfedern 31, 32 weiter komprimiert werden. Wenn der Kolben 12 in der Zeichnung nach rechts verschoben wird, dann stützt sich der Stützteller 24 gegen den Ringrand 29 des Gegenhaltekolbens 30 ab, wird also ebenfalls festgehalten, während der Stützteller 23 von dem Kolben 12 mitgenommen wird. Auch in diesem Fall werden also die beiden Druckfedern 31, 32 weiter komprimiert, d.h. sie üben eine der Verschiebebewegung des Kolbens 12 entgegenwirkende Kraft auf den Kolben 12 aus.Two spring support plates 23, 24 are arranged on the receiving section 21. One of the support plates 23 facing the piston 12 lies in the illustrated central position of the piston 12 with an inner ring section 25 against the piston 12 and with an outer flange ring 26 against a stop 27 fixed to the housing, which is formed by a wall delimiting the second control chamber 19. The other spring support plate 24 lies with an inner ring portion 25 'against a locking ring 28 on the section 21. Furthermore, the support plate 24 is supported on its side facing away from the piston 12 against an annular rim 29 of a counter-holding piston 30. Between the two support plates 23, 24 there are two prestressed helical compression springs 31, 32. If the piston 12 is shifted to the left in the drawing in the manner already mentioned, then the left support plate 23 is supported with its flange ring 26 against the stop fixed to the housing 27, remains in its starting position. The other support plate 24 is carried by the locking ring 28, so that the two compression springs 31, 32 are further compressed. If the piston 12 is shifted to the right in the drawing, the support plate 24 is supported against the ring rim 29 of the counter-holding piston 30, is thus also held in place while the support plate 23 is carried by the piston 12. In this case, too, the two compression springs 31, 32 are compressed further, ie they exert a force on the piston 12 which counteracts the displacement movement of the piston 12.

Die geschilderten Betätigungen des als Ventilschieber dienenden Kolbens 12 erfolgen durch entsprechende Beaufschlagung des ersten Steuerraums 17 bzw. des zweiten Steuerraums 19 mit Steuerdruck, wobei der jeweils andere Steuerraum 19 bzw. 17 druckentlastet ist. Hierzu ist der erste Steuerraum 17 über eine Steuer-Leitung 33 mit einem manuell bedienbaren Vorsteuerventil 34 verbunden, das wiederum an eine als Steuerdruckmittelquelle dienende Pumpe 35 über eine Versorgungs-Leitung 36 angeschlossen ist. Der zweite Steuerraum 19 ist über eine Steuer-Leitung 37 mit einem grundsätzlich gleichartig ausgebildeten, ebenfalls manuell betätigbaren Vorsteuerventil 38 verbunden, das ebenfalls an die Versorgungs-Leitung 36 angeschlossen ist. Beide Vorsteuerventile 34, 38 sind über eine Rücklauf-Leitung 39 an den Tank 10 angeschlossen. Beide Vorsteuerventile 34, 38 können selbstverständlich in üblicher Weise zu einem Ventil zusammengefaßt sein, wobei dann auch nur ein Betätigungshebel 40 vorgesehen sein müßte, der zur Druckbeaufschlagung der ersten Steuerkammer 17 aus seiner Mittellage in eine Richtung und zur Druckbeaufschlagung der zweiten Steuerkammer 19 in die andere Richtung verschwenkt würde.The described actuations of the piston 12 serving as a valve slide take place by appropriately applying control pressure to the first control chamber 17 and the second control chamber 19, the other control chamber 19 and 17 being relieved of pressure. For this purpose, the first control chamber 17 is connected via a control line 33 to a manually operated pilot valve 34, which in turn is connected to a pump 35 serving as a control pressure medium source via a supply line 36. The second control chamber 19 is connected via a control line 37 to a basically similarly designed, likewise manually operated pilot valve 38, which is also connected to the supply line 36. Both pilot valves 34, 38 are connected to the tank 10 via a return line 39. Both pilot valves 34, 38 can of course be combined in a conventional manner to form a valve, in which case only one actuating lever 40 would then have to be provided, which for pressurizing the first control chamber 17 from its central position in one direction and for pressurizing the second control chamber 19 in the other Direction would be pivoted.

Der Gegenhaltekolben 30 ist in seinem mittleren zylindrischen Abschnitt 41 mittels einer Dichtung 42 abgedichtet in einer zur Achse 22 koaxialen Zylinderführung 43 verschiebbar geführt. Auf seiner dem zweiten Steuerraum 19 und seinem Ringrand 29 entgegengesetzten Seite weist er einen nach außen über den zylindrischen Abschnitt 41 vorstehenden Ringbund 44 auf, der in der dargestellten Ruhelage gegen einen gehäusefesten Anschlag 45 anliegt und damit ein Verschieben des Gegenhaltekolbens 30 in Richtung zum Kolben 12 hin begrenzt. Diese Seite des Gegenhaltekolbens 30 befindet sich in einer Steuerkammer 46, die von der Versorgungs-Leitung 36 her ständig mit dem vollen also maximalen Steuerdruck von der Pumpe 35 beaufschlagt wird. Die Steuerkammer 46 ist mittels einer Verschlußschraube 47 verschlossen, gegen die sich eine als Schraubendruckfeder ausgebildete Vorspannfeder 48 abstützt, die sich gegen den Gegenhaltekolben 30 abstützt und diesen in Richtung auf den Kolben 12 drückt, also den Ringbund 44 gegen den Anschlag 45 drückt. Die Steuerkammer 46 ist weiterhin über eine Rücklauf-Leitung 49, in der sich ein Druckbegrenzungsventil 50 befindet, an den Tank 10 angeschlossen. Der Durchmesser D1 des zylindrischen Kolbens 12 ist größer als der Durchmesser D2 des zylindrischen Abschnitts 41 des Gegenhaltekolbens 30.The counter-holding piston 30 is guided in its central cylindrical section 41 in a sealed manner by means of a seal 42 in a cylinder guide 43 coaxial with the axis 22. On its side opposite the second control chamber 19 and its ring rim 29, it has an annular collar 44 projecting outward beyond the cylindrical section 41, which in the rest position shown rests against a stop 45 fixed to the housing and thus a displacement of the counter-holding piston 30 in the direction of the piston 12 limited. This side of the counter-holding piston 30 is located in a control chamber 46 which is constantly acted upon by the supply line 36 with the full, ie maximum, control pressure from the pump 35. The control chamber 46 is closed by means of a locking screw 47 against which a biasing spring 48 designed as a helical compression spring is supported, which is supported against the counter-holding piston 30 and presses it in the direction of the piston 12, that is to say it presses the annular collar 44 against the stop 45. The control chamber 46 is also connected to the tank 10 via a return line 49, in which there is a pressure relief valve 50. The diameter D1 of the cylindrical piston 12 is larger than the diameter D2 of the cylindrical section 41 of the counter-holding piston 30.

Die Vorsteuerventile 34, 38 sind als stufenlos arbeitende Druckminderventile ausgebildet, so daß die Steuerräume 17, 19 wahlweise und jeweils abwechselnd mit unterschiedlichem Steuerdruck beaufschlagt werden können, der für die geschilderte Beaufschlagung des jeweiligen Kolbenringraums 5 zum Senken der Last bzw. zum Beaufschlagen des jeweiligen Kolbenraums 6 zum Heben der Last kleiner ist als der von der Pumpe 35 gelieferte maximale Steuerdruck in der Steuerkammer 46. Obwohl die im Steuerraum 17 befindliche wirksame Fläche des Kolbens 12 mit dem Durchmesser D1 größer ist als die dem Durchmesser D2 entsprechende wirksame Fläche des Gegenhaltekolbens 30, verbleibt dieser in seiner in der Zeichnung dargestellten Haltestellung. Wenn also durch Beaufschlagung des jeweiligen Kolbenringraums 5 die Last gesenkt werden soll, dann wird das Vorsteuerventil 34 betätigt, wodurch der erste Steuerraum 17 mit Steuerflüssigkeit beaufschlagt wird, deren Druck dem Maß der Betätigung des Betätigungshebels 40 entspricht, deren Druck also nur einem Teil-Druck des maximalen Steuerdrucks entspricht. Der Kolben 12 wird hierbei in Richtung auf den zweiten Steuerraum 19 verschoben, wobei der Feder-Stützteller 23 mitgenommen wird, während der andere Feder-Stützteller 24 in seiner gegen den Ringrand 29 des Gegenhaltekolbens 30 anliegenden Stellung verbleibt. Da diese auf den Gegenhaltekolben 30 von der Steuerkammer 46 und der Vorspannfeder 48 her wirkende Kraft größer ist, als die vom Kolben 12 auf ihn ausgeübte Kraft, verbleibt der Gegenhaltekolben 30 in seiner dargestellten Haltestellung und bildet also ein Widerlager für den Feder-Stützteller 24. Die beiden Druckfedern 31, 32 werden weiter zusammengedrückt, bis sich ein Gleichgewicht zwischen der vom ersten Steuerraum 17 her wirkenden Kraft und der von den Druckfedern 31, 32 ausgeübten Gegenkraft einstellt. Entsprechend dieser Verschiebung des als Ventilschiebers dienenden Kolbens 12 wird der Ventilblock 13 angesteuert, so daß der jeweilige Kolbenringraum 5 über die Leitung 7 mit Druckmittel beaufschlagt wird. Der jeweilige Kolbenraum 6 ist über die Leitung 8, den Ventilblock 13 und die Rücklauf-Leitung 14 an den Tank 10 angeschlossen.The pilot valves 34, 38 are designed as continuously working pressure reducing valves, so that the control spaces 17, 19 alternately and in each case can be acted upon with different control pressure, which is smaller than the maximum control pressure supplied by the pump 35 in the control chamber 46 for the described loading of the respective piston annulus 5 for lowering the load or for loading the respective piston chamber 6 for lifting the load effective area of the piston 12 with the diameter D1 located in the control chamber 17 is larger than the effective area of the counter-holding piston 30 corresponding to the diameter D2, this remains in its holding position shown in the drawing. So if the load is to be reduced by acting on the respective piston annulus 5, then the pilot valve 34 is actuated, whereby the first control chamber 17 is acted upon with control liquid, the pressure of which corresponds to the degree of actuation of the actuating lever 40, the pressure of which is therefore only a partial pressure corresponds to the maximum control pressure. The piston 12 is displaced in the direction of the second control chamber 19, the spring support plate 23 being carried along, while the other spring support plate 24 remains in its position against the ring rim 29 of the counter-holding piston 30. Since this force acting on the counter-holding piston 30 from the control chamber 46 and the biasing spring 48 is greater than the force exerted on it by the piston 12, the counter-holding piston 30 remains in the holding position shown and thus forms an abutment for the spring support plate 24. The two compression springs 31, 32 are further compressed until there is a balance between the force acting from the first control chamber 17 and that from the compression springs 31, 32 sets the counterforce exerted. Corresponding to this displacement of the piston 12 serving as a valve spool, the valve block 13 is actuated so that the respective piston annulus 5 is acted upon by pressure medium via the line 7. The respective piston chamber 6 is connected to the tank 10 via the line 8, the valve block 13 and the return line 14.

Wenn dagegen die Last gehoben, also der jeweilige Kolbenraum 6 beaufschlagt werden soll, dann wird das Vorsteuerventil 38 entsprechend geöffnet, so daß in den zweiten Steuerraum 19 Steuerflüssigkeit gelangt. Diese wirkt ebenfalls über eine dem Durchmesser D1 entsprechende Fläche auf den Kolben 12 und verschiebt diesen in Richtung zum ersten Steuerraum 17 hin, wobei der Feder-Stützteller 23 in seiner Stellung am Anschlag 27 verbleibt. Demgegenüber wird der andere Stützteller 24 an dem Sicherungsring 28 mitgenommen, wodurch wiederum die beiden Druckfedern 31, 32 zusammengedrückt werden. Die Verschiebebewegung erfolgt wieder so lange, bis sich das bereits angesprochene Kräftegleichgewicht einstellt. Da der Druck in der Steuerkammer 46 größer ist als im zweiten Steuerraum 19, verbleibt der Gegenhaltekolben 30 in seiner Haltestellung. Die Vorsteuerventile 34, 38 sind jeweils in ihrer nichtbetätigten Lage über die Rücklauf-Leitung 39 an den Tank 10 angeschlossen, so daß bei Verschiebungen des Kolbens 12 die im jeweils nicht beaufschlagten Steuerraum 17 bzw. 19 verdrängte Steuerflüssigkeit abfließen kann.If, on the other hand, the load is to be lifted, that is to say the respective piston chamber 6 is to be acted upon, then the pilot valve 38 is opened accordingly, so that control fluid 19 reaches the second control chamber. This also acts on the piston 12 via a surface corresponding to the diameter D1 and displaces it in the direction of the first control chamber 17, the spring support plate 23 remaining in its position on the stop 27. In contrast, the other support plate 24 is carried on the locking ring 28, which in turn compresses the two compression springs 31, 32. The shifting movement continues until the already mentioned balance of forces is established. Since the pressure in the control chamber 46 is greater than in the second control chamber 19, the counter-holding piston 30 remains in its holding position. The pilot valves 34, 38 are each connected in their non-actuated position via the return line 39 to the tank 10, so that when the piston 12 shifts, the control liquid 17 or 19 displaced in the non-pressurized control chamber 17 or 19 can flow out.

Wenn die Antriebe 1 in eine sogenannte Schwimmstellung gebracht werden sollen, in der der jeweilige Kolbenraum 6 und der jeweilige Kolbenringraum 5 mit dem Tank 10 verbunden, also kurzgeschlossen sind, dann muß der als Ventilschieber dienende Kolben 12 zur entsprechenden Betätigung des Ventilblocks 13 in eine Extremlage verschoben werden. Diese Extremlage entspricht einer noch weiter nach rechts verschobenen Stellung. Hierzu wird der erste Steuerraum 17 durch vollständiges Öffnen des Steuerventils 34 mit dem vollen von der Pumpe 35 gelieferten Steuerdruck beaufschlagt. Da in diesem die auf den Kolben 12 in Richtung auf den Gegenhaltekolben 30 wirkende Kraft größer ist als die in entgegengesetzter Richtung von der Steuerkammer 46 auf letzteren wirkende Kraft, wird der Kolben 12 so weit verschoben, bis der Aufnahmeabschnitt 21 gegen den zugewandten Boden 51 des Gegenhaltekolbens 30 anliegt. Bei der weiteren Bewegung drückt dann der Kolben 12 den Gegenhaltekolben 30 in Richtung auf die Steuerkammer 46 in eine Ausweichstellung. Hierbei wird die hierin befindliche unter dem vollen, also maximalen Steuerdruck stehende Steuerflüssigkeit über das Druckbegrenzungsventil 50 in den Tank 10 gedrückt. Der Gegenhaltekolben 30 kann also die Bewegung des Kolbens 12 teilweise mitmachen.If the drives 1 in a so-called floating position are to be brought, in which the respective piston chamber 6 and the respective piston ring chamber 5 are connected to the tank 10, that is to say short-circuited, then the piston 12 serving as a valve slide must be moved to an extreme position for the corresponding actuation of the valve block 13. This extreme position corresponds to a position shifted further to the right. For this purpose, the full control pressure supplied by the pump 35 is applied to the first control chamber 17 by completely opening the control valve 34. Since in this the force acting on the piston 12 in the direction of the counter-holding piston 30 is greater than the force acting on the latter in the opposite direction from the control chamber 46, the piston 12 is displaced until the receiving section 21 against the facing bottom 51 of the Counter piston 30 abuts. During the further movement, the piston 12 then presses the counter-holding piston 30 in the direction of the control chamber 46 into an evasive position. In this case, the control liquid located here under the full, that is to say maximum control pressure, is pressed into the tank 10 via the pressure limiting valve 50. The counter-holding piston 30 can thus partially participate in the movement of the piston 12.

Der maximal mögliche Hub H1 des Kolbens 12 gegenüber dem Gegenhaltekolben 30 ist durch den Abstand zwischen dem Aufnahme-Abschnitt 21 und dem Boden 51 des Gegenhaltekolbens 30 vorgegeben. Um diesen Hub H1 kann der Kolben 12 maximal verschoben werden, wenn die Funktion "Senken der Last" angesteuert wird. Zusätzlich kann der Kolben 12 dann noch um den Hub H2 verschoben werden, der durch den Abstand zwischen Gegenhaltekolben 30 und Verschlußschraube 47 vorgegeben ist. Dieser zweite Hub H2 kann dann also für die Funktion "Schwimmstellung" angesteuert werden. Er entspricht dem Hub des Gegenhaltekolbens 30 von der Haltestellung in die Ausweichstellung.The maximum possible stroke H1 of the piston 12 relative to the counter-holding piston 30 is predetermined by the distance between the receiving section 21 and the base 51 of the counter-holding piston 30. The piston 12 can be maximally displaced by this stroke H1 if the "lowering the load" function is activated. In addition, the piston 12 can then be moved by the stroke H2 are determined by the distance between the counter-holding piston 30 and the locking screw 47. This second stroke H2 can then be controlled for the "floating position" function. It corresponds to the stroke of the counter-holding piston 30 from the holding position into the evasive position.

Das Druckbegrenzungsventil 50 hat im übrigen die Hauptfunktion, den von der Pumpe 35 gelieferten Steuerdruck konstant zu halten. Wird er überschritten, öffnet das Druckbegrenzungsventil 50 und läßt den Druck zum Tank 10 hin sich abbauen. Der maximale Steuerdruck steht nicht nur ständig in der Steuerkammer 46, sondern auch in der Versorgungs-Leitung 36 vor den Vorsteuerventilen 34, 38 an.The pressure limiting valve 50 also has the main function of keeping the control pressure supplied by the pump 35 constant. If it is exceeded, the pressure relief valve 50 opens and the pressure to the tank 10 can be reduced. The maximum control pressure is not only constantly present in the control chamber 46, but also in the supply line 36 upstream of the pilot valves 34, 38.

Claims (2)

  1. Multiport valve (11) for the control of the working pressure medium paths (7, 8, 14, 15) between a consumer (1) and a working pressure medium source (9) or a tank (10), each having a control chamber (17, 19) disposed on each end (16, 18) of a valve slide (12), which are connectable with a control pressure source (35), a maximum control pressure being kept constant by means of a pressure control valve (50), having a restraining piston (30) delimiting a second control chamber (19) and of which the side facing away from the second control chamber (19) is charged with maximum control pressure via a control chamber (46) connected with the control pressure source (35), the restraining piston (30) being movable between a holding position and a deflected position, having at least one pressure spring (31, 32) disposed in the second control chamber (19) and supported on the valve slide (12) and the restraining piston (30) and at least one pilot valve (34, 38) for setting the control pressure in the control chambers (17, 19), where, starting at a center position in which the pressure medium paths (7, 8) to the consumer (1) are locked and the restraining piston (30) is in the holding position and charged with the maximum control pressure, the valve slide (12) is displaceable against the force of the at least one pressure spring (31, 32) in both directions into in each case at least one working position, and where, starting from a working position, in which the second control chamber (19) abutting against the restraining piston (30) is pressure-relieved, the restraining piston (30) is displaceable into the deflected position, in which the valve slide (12) supported by means of at least one pressure spring (31, 32) on the restraining piston (30), is movable by the control pressure charging the first control chamber (17) into a floating position of the consumer (1), in which the working chambers (5 and 6) of the consumer (1) are connected with each other, characterized in that the valve slide (12) in the first control chamber (17) has a greater diameter than the restraining piston (30) in the form of a closed piston such that the force in the first control chamber (17) acting on the valve slide (12) in the direction of the restraining piston (30), at least during maximum control pressure, is greater than the force acting in the opposite direction from the control chamber (46) on the restraining piston (30).
  2. Multiport valve in accordance with claim 1, characterized in that the restraining piston (30) is loaded by a pre-stressing spring (48) on its side facing the control chamber (46).
EP90103290A 1989-03-25 1990-02-21 Multiple way valve Expired - Lifetime EP0389787B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3909988 1989-03-25
DE3909988A DE3909988C1 (en) 1989-03-25 1989-03-25

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EP0389787A2 EP0389787A2 (en) 1990-10-03
EP0389787A3 EP0389787A3 (en) 1991-04-10
EP0389787B1 true EP0389787B1 (en) 1992-12-16

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ID=6377293

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EP90103290A Expired - Lifetime EP0389787B1 (en) 1989-03-25 1990-02-21 Multiple way valve

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US (1) US5038825A (en)
EP (1) EP0389787B1 (en)
JP (1) JPH02283903A (en)
DE (2) DE3909988C1 (en)

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE4031628C2 (en) * 1990-10-05 1995-07-13 Rexroth Mannesmann Gmbh 3-way control valve
JP3119722B2 (en) * 1992-05-25 2000-12-25 株式会社小松製作所 Hydraulic circuit of 4-position closed center switching valve by pressure proportional control valve
US5275086A (en) * 1992-08-27 1994-01-04 Unlimited Solutions, Inc. Fluid actuator with internal pressure relief valve
CN104214155A (en) * 2014-08-19 2014-12-17 合肥长源液压股份有限公司 Integral type multi-way valve provided with integral type hydraulic locks
JP2022163935A (en) * 2021-04-15 2022-10-27 Smc株式会社 Four-position selector valve

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4355660A (en) * 1980-04-15 1982-10-26 General Signal Corporation Pneumatically controlled, four position hydraulic valve
DE3232350A1 (en) * 1982-04-21 1984-03-01 Mannesmann Rexroth GmbH, 8770 Lohr Device for actuating a sliding body, in particular the piston-type slide of a directional control valve
DE3508340A1 (en) * 1985-03-08 1986-09-11 Mannesmann Rexroth GmbH, 8770 Lohr Multi-way valve

Also Published As

Publication number Publication date
US5038825A (en) 1991-08-13
DE59000584D1 (en) 1993-01-28
DE3909988C1 (en) 1990-05-23
EP0389787A3 (en) 1991-04-10
EP0389787A2 (en) 1990-10-03
JPH02283903A (en) 1990-11-21

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