EP0149787B2 - Feed controlling device for a variable hydropump - Google Patents

Feed controlling device for a variable hydropump Download PDF

Info

Publication number
EP0149787B2
EP0149787B2 EP84115198A EP84115198A EP0149787B2 EP 0149787 B2 EP0149787 B2 EP 0149787B2 EP 84115198 A EP84115198 A EP 84115198A EP 84115198 A EP84115198 A EP 84115198A EP 0149787 B2 EP0149787 B2 EP 0149787B2
Authority
EP
European Patent Office
Prior art keywords
valve
pressure
control
torque
pump
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
EP84115198A
Other languages
German (de)
French (fr)
Other versions
EP0149787A3 (en
EP0149787A2 (en
EP0149787B1 (en
Inventor
Gerhard Beutler
Heinz Berthold
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.)
Brueninghaus Hydraulik GmbH
Original Assignee
Brueninghaus Hydraulik GmbH
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation
First worldwide family litigation filed litigation Critical https://patents.darts-ip.com/?family=25816438&utm_source=google_patent&utm_medium=platform_link&utm_campaign=public_patent_search&patent=EP0149787(B2) "Global patent litigation dataset” by Darts-ip is licensed under a Creative Commons Attribution 4.0 International License.
Application filed by Brueninghaus Hydraulik GmbH filed Critical Brueninghaus Hydraulik GmbH
Publication of EP0149787A2 publication Critical patent/EP0149787A2/en
Publication of EP0149787A3 publication Critical patent/EP0149787A3/en
Application granted granted Critical
Publication of EP0149787B1 publication Critical patent/EP0149787B1/en
Publication of EP0149787B2 publication Critical patent/EP0149787B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B1/00—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders
    • F04B1/12—Multi-cylinder machines or pumps characterised by number or arrangement of cylinders having cylinder axes coaxial with, or parallel or inclined to, main shaft axis
    • F04B1/26—Control
    • F04B1/30—Control of machines or pumps with rotary cylinder blocks
    • F04B1/32—Control of machines or pumps with rotary cylinder blocks by varying the relative positions of a swash plate and a cylinder block
    • F04B1/324—Control of machines or pumps with rotary cylinder blocks by varying the relative positions of a swash plate and a cylinder block by changing the inclination of the swash plate
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B49/00—Control, e.g. of pump delivery, or pump pressure of, or safety measures for, machines, pumps, or pumping installations, not otherwise provided for, or of interest apart from, groups F04B1/00 - F04B47/00
    • F04B49/08—Regulating by delivery pressure

Definitions

  • the invention relates to a flow control device according to the preamble of claim 1.
  • the torque valve is followed by the control valve, which acts as a pressure compensator and primarily serves to adjust the delivery rate.
  • the control valve acts as a pressure compensator and primarily serves to adjust the delivery rate.
  • DE-A 20 38 968 discloses a power control device for two or more hydraulic pumps and, moreover, the torque valve is not arranged in such a way that it connects the operating pressure control line depending on the pressure in the operating pressure control line and the preload of the measuring spring set with the unpressurized outlet.
  • a torque valve is known per se from FR-A 1,318,661, the spring of which is connected to the pump frame, but this known embodiment relates to a manually adjustable pump and, moreover, the torque valve is not controlled as a function of the pressure in the operating pressure control line.
  • the design and arrangement of the torque valve according to the invention in a flow control means that the torque valve can be attached to the hydraulic pump as a separate assembly and a driver pin of the pump actuator acts directly on the torque valve to change the preload of the measuring spring / measuring spring set depending on the flow rate setting. Since the torque characteristic is determined solely by the design of the characteristic of the measuring spring or the measuring spring set and the measuring spring is set directly via the driver pin, the preload of the measuring spring or the measuring spring set can be adjusted from outside by a stop in the torque valve by means of a handle.
  • any number of different torque characteristics can be preselected and also set or adjusted during operation, which is particularly advantageous when the pump torque is optimally adapted to the torque of the drive machine driving the pump.
  • a quick adaptation to any application is possible and such a moment valve can be used for pumps of different sizes and capacities without additional adaptation measures being necessary.
  • the stop in the torque valve can expediently be arranged on the end of the valve housing and be detachable for the exchange of the measuring spring / measuring spring set.
  • the torque control means is also suitable as total control for two or more drive side mechanically coupled hydraulic pumps, if according to the invention that the closing member of the momen - tenventils each pump from the sum of the pressure is applied in the operating pressure control line of the individual pump and the pressure in the operating pressure line of the other pump (s) and that each torque valve connects the operating pressure control line of its pump depending on the total operating pressure and the preload of its measuring spring with the unpressurized outlet.
  • the closing elements of the torque valves have several measuring surfaces which act in parallel and are each acted upon by the operating pressure of one of the pumps.
  • the hydraulic pump 1 is driven via the shaft 2 by a drive, not shown.
  • the pump actuator consists of a swivel element 3, the swivel angle a of which is proportional to the stroke volume of the hydraulic pump 1.
  • the servo actuator, not shown, for adjusting the swivel angle a comprises a spring 4 and a pressurizable actuating piston 5, the spring 4 adjusting the hydraulic pump 1 in the direction of the maximum swivel angle a, that is to say the maximum delivery volume.
  • An actuating piston 6 of the actuating device which can also be functionally combined with the piston 5, takes over the back part function in the direction of a smaller pivot angle a.
  • the control pressure acting on the piston 6 in the line 7 is removed via a control valve 8 and the line 9 from the delivery pressure line 10 of the hydraulic pump 1.
  • a common pressure relief valve 11 is located in series with the control valve 8.
  • the control valve 8 is designed as a pressure compensator and is acted upon on the one hand by the delivery pressure and on the other hand by a control pressure in the operating pressure control line 12, which controls the operating pressure of the hydraulic pump 1 behind a throttle 13 which limits the control flow operating pressure line 14 decreases after an optionally adjustable flow restrictor 15.
  • a moment valve 16 is acted upon on the one hand by the pressure in the control line 12 and on the other hand by a measuring spring or measuring spring set 17, the pretension of which is determined by the position of the piston 6 or the pump actuator 3.
  • the torque valve 16 can connect the control line 12 to the unpressurized outlet 18.
  • the operating pressure in the control line 12 reaches the value set on the torque valve 16 so that it begins to open, a pressure drop occurs at the control slide of the control valve 8 via the throttle 13.
  • the control slide is moved into the switching position 11 and supplies the piston 6 with Control pressure, so that it strives to adjust the actuator 3 of the hydraulic pump 1 in the direction of smaller flow rates.
  • the measuring spring 17 or the measuring spring set of the torque valve 16 is biased.
  • the measuring springs or the measuring spring set are designed in their spring characteristics. that, depending on the preload, an envelope is created in the theoretically desired power hyperbola.
  • a defined swivel angle a corresponds to a defined operating pressure in line 10.
  • the delivery rate setting of the hydraulic pump 1 in the area in which the torque control, that is to say the torque valve 16 has not yet responded is carried out in the usual way via the delivery rate throttle 15 and requires no special explanation.
  • FIG. 2 shows an embodiment of a torque valve 16 in its assignment to the pivotable pump actuator of an inclined-axis axial piston pump.
  • the pivotable actuator has a driver pin 20 projecting into the torque valve 16.
  • the torque valve 16 is designed as a seat valve arranged in a valve housing 21 with a valve cone 22 as a closing element, which is acted upon by a measuring spring set 17 formed from the springs 23 and 24.
  • the valve seat for the valve cone 22 is formed on a valve body 25 which is displaceably arranged in the valve housing 21 and on which the driver pin 20 of the pump actuator acts.
  • the valve body is acted upon by a spring 26 which is supported in the valve housing 21 and holds the valve body 25 in positive engagement with the driver pin 20.
  • the spring 23 of the measuring spring set 17 is supported on a stop 27 and the spring 24 on an adjusting screw .28 in the stop 27.
  • the stop 27 is screwed into the end of the valve housing 21. Due to the rotational position of the stop 27, the preload of the measuring spring set 17 and thus the position of the desired torque characteristics and the response point of the torque valve 16 can be adjusted.
  • the stop 27 has a handle 29. The course of the torque characteristics or the spring characteristic can be done by changing the preload of the spring 24 with the help of the adjusting screw 28.
  • the pressure present in the operating pressure control line 12 acts through the channel 30 in the valve body25 on the closing member 22 against the force of the measuring spring set 17.
  • the width of the valve seat determines the effective measuring area on the closing member 22 for the pressure in line 12. If the force exerted on the measuring surface by the pressure in line 12 exceeds the prestressing force of the measuring spring set 17, the valve cone of the closing member 22 lifts off the valve seat in the valve body 25 and opens the control line 12 to the unpressurized outlet, formed by the interior 31 of the valve housing 21 which is fixedly connected to the hydraulic pump, the interior 31 being connected to the unpressurized interior 32 of the hydraulic pump stands.
  • the driving pin 20 moves the valve body 25 in FIG. 2 to the right against the closing member 22 and thus increases the preload of the spring set 17 in accordance with the desired course of the torque characteristic.
  • the control device according to the invention is shown as a total torque control for two hydraulic pumps 33, 34, the drive shafts of which are driven directly or via a corresponding transfer gear 35 (only indicated schematically by a dash) by a common drive machine, not shown.
  • the control devices for the individual pumps correspond to the control device shown in FIG.
  • the same parts are provided with the same reference numerals and are not explained again.
  • Only the torque valves denoted by 16 in FIG. 1 are designed here as total torque valves 36 and differ from the torque valve 16 in that the closing element 22 according to FIG. 4 has an additional measuring surface 37.
  • the operating pressure of the other pump acts on this measuring surface 37 via a control line 38, 39.
  • the response that is to say the opening of the momentary valves 36 for the control pressure medium in the lines 12 for the unpressurized discharge, is thus dependent on the sum of the operating pressures.
  • Such regulations are necessary, for example, if two hydraulic pumps are driven by a common drive shaft or via a transfer case and the sum of the two torques of the pumps must not exceed the drive torque.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Control Of Positive-Displacement Pumps (AREA)
  • Fluid-Pressure Circuits (AREA)

Description

Die Erfindung bezieht sich auf eine Fördermengen-Regeleinrichtung nach dem Oberbegriff des Anspruches 1.The invention relates to a flow control device according to the preamble of claim 1.

Aus dem Prospekt Nr. A 536/1.81 "Konstant- und Verstell-Kolbenpumpen Pf,PV + PVG" der Firma GEBR. BOEHRINGER GMBH, Produktlinie Hydrokraft (Seite 10, zweite Bildreihe von oben) ist eine gattungsgemäße Regeleinrichtung bekannt, bei der ein Momentenventil vorzusehen ist, dessen Schließkraft von einer Meßfeder bestimmt ist, die mit dem Pumpenstellglied wirkverbunden ist und in Abhängigkeit von der Fördermengeneinstellung über eine Steuerkurve vorgespanntwird, und das den das Steuerventil beaufschlagenden Druck regelt.From brochure No. A 536 / 1.81 "Constant and variable piston pumps Pf, PV + PVG" from GEBR. BOEHRINGER GMBH, Hydrokraft product line (page 10, second row of images from above), a generic control device is known in which a torque valve is to be provided, the closing force of which is determined by a measuring spring which is operatively connected to the pump actuator and depending on the delivery rate setting via a control curve is biased and regulates the pressure applied to the control valve.

Bei derartigen Regeleinrichtungen besteht eine direkte Funktionsbeziehung zwischen dem Hubvolumen der Pumpe und der Steuerung des Betriebsdrucks, der das Steuerventil betätigt, wodurch eine verlustarme Momentenregelung gegeben ist, weil die Momentenkennlinie nicht durch ein Drosselsystem durch Absenken des Betriebsdruckes festgelegt wird, sondem ausschließlich durch Veränderung der Federvorspannung am Momentenventil, das heißt durch Auslegung der Meßfeder bzw. des Meßfedersatzes. Für eine Momentenregelung gilt die Beziehung, daß das Produkt aus Betriebsdruck und Hubvolumen der Pumpe konstant sein muß. Ein Maß für das Hubvolumen einer Hydropumpe ist die Stellung des die Pumpenfördermenge einstellenden Pumpenstellgliedes, das erfindungsgemäß mittels der/dem Feder/Meßfedersatz mit dem Momentenventil verbunden ist. Außerdem ist dem Momentenventil das als Druckwaage wirkende, primär der Fördermengeneinstellung dienende Steuerventil nachgeschaltet. Dies hat den Vorteil, daß unterhalb der ansprechenden Momentenregelung am Momentenventil die Förderstromeinstellung unbeeinflußt bleibt. Ein weiterer wesentlicher Vorteil ist, daß kurze Ausschwenkzeiten (Einstellzeiten für die Pumpe auf maximale Fördermenge) ermöglicht sind, da der Stellkolben des Stellgerätes unmittelbar mit dem Ablauf verbunden werden kann.In such control devices, there is a direct functional relationship between the stroke volume of the pump and the control of the operating pressure that actuates the control valve, which results in low-loss torque control because the torque characteristic is not determined by a throttle system by lowering the operating pressure, but only by changing the spring preload on the torque valve, i.e. by designing the measuring spring or the measuring spring set. For a torque control, the relationship applies that the product of the operating pressure and the stroke volume of the pump must be constant. A measure of the stroke volume of a hydraulic pump is the position of the pump actuator adjusting the pump delivery rate, which is connected according to the invention to the torque valve by means of the spring / measuring spring set. In addition, the torque valve is followed by the control valve, which acts as a pressure compensator and primarily serves to adjust the delivery rate. This has the advantage that below the responsive torque control on the torque valve, the flow rate setting remains unaffected. Another important advantage is that short swiveling times (setting times for the pump to the maximum flow rate) are made possible, since the actuating piston of the actuating device can be connected directly to the drain.

Es ist zwar aus der DE-A 15 28 550 und aus der DE-A 20 38 968 ansich bekannt, zur Fördermengen-Regelung ein Momentenventil mittels eines Meßfedersatzes mit dem Pumpenstellglied zu verbinden, jedoch bestehen gattungsmäßige Unterschiede.Although it is known from DE-A 15 28 550 and from DE-A 20 38 968 per se to connect a torque valve to the pump actuator by means of a measuring spring set to regulate the delivery rate, there are generic differences.

Bei der Ausgestaltung gemäß DE-A 15 28 550 erfolgt keine Momentenregelung, sondern es wird der Pumpendruck so eingestellt, daß er den maximalen Betriebsdruck um einen bestimmten Wert nicht überschreitet. DE-A 20 38 968 offenbart eine Leistungs-Regelvorrichtung für zwei oder mehrere Hydropumpen und außerdem ist das Momentenventil nicht so angeordnet, daß es die Betriebsdruck-Steuerleitung in Abhängigkeit vom Druck in der Betriebsdruck Steuerleitung und der Vorspannung des Meßfedersatzes mit dem drucklosen Ablauf verbindet.In the embodiment according to DE-A 15 28 550 there is no torque control, but the pump pressure is set so that it does not exceed the maximum operating pressure by a certain value. DE-A 20 38 968 discloses a power control device for two or more hydraulic pumps and, moreover, the torque valve is not arranged in such a way that it connects the operating pressure control line depending on the pressure in the operating pressure control line and the preload of the measuring spring set with the unpressurized outlet.

Außerdem ist aus FR-A 1,318,661 ein Momentenventil ansich bekannt, dessen Feder mit dem Pumpengestell verbunden ist, jedoch bezieht sich diese bekannte Ausgestaltung auf eine manuell verstellbare Pumpe, und außerdem wird das Momentenventil nicht in Abhängigkeit vom Druck in der Betriebsdruck-Steuerleitung gesteuert.In addition, a torque valve is known per se from FR-A 1,318,661, the spring of which is connected to the pump frame, but this known embodiment relates to a manually adjustable pump and, moreover, the torque valve is not controlled as a function of the pressure in the operating pressure control line.

Es ist Aufgabe der Erfindung, eine Fördermengen-Regeleinrichtung der genannten Art bzw. dessen Momentenventil so weiterzubilden, daß es als Momentenventil für Pumpen unterschiedlicher Größe und Leistung verwendet werden kann, wobei diese Pumpen lediglich im verstellweg für das Pumpenstellglied übereinstimmen müssen, also beispielsweise im Schwenkwinkel bei verstellbaren Schrägachsenpumpen.It is an object of the invention to develop a flow control device of the type mentioned or its torque valve so that it can be used as a torque valve for pumps of different sizes and capacities, these pumps only having to agree in the adjustment path for the pump actuator, for example in the pivoting angle with adjustable inclined-axis pumps.

Diese Aufgabe wird durch die kennzeichnenden Merkmale des Anspruches 1 gelöst.This object is achieved by the characterizing features of claim 1.

Die erfindungsgemäße Ausbildung und Anordnung des Momentenventiles in einer Fördermengenregelung gestattet es, daß das Momentenventil als gesonderte Baugruppe an der Hydropumpe befestigt werden kann und ein Mitnehmerstift des Pumpenstellgliedes unmittelbar am Momentenventil zur Änderung der Vorspannung der Meßfeder/Meßfedersatzes in Abhängigkeit von der Fördermengeneinstellung angreift. Da die Momentenkennlinie allein durch Auslegung der Charakteristik der Meßfeder bzw. des Meßfedersatzes bestimmt ist und die Meßfeder unmittelbar über den Mitnehmerstift eingestellt wird, ist die Vorspannung der Meßfeder bzw. des Meßfedersatzes durch einen Anschlag im Momentenventil mittels einer Handhabe von außen einstellbar. Durch die von außen einstellbare Meßfeder bzw. Meßfedersatz können beliebig viele unterschiedliche Momentenkennlinien vorgewählt werden und auch während des Betriebes eingestellt bzw. verstellt werden, was besonders bei der optimalen Anpassung des Pumpenmomentes an das Moment der die Pumpe antreibenden Antriebsmaschine von Vorteil ist. Eine schnelle Anpassung an beliebige Anwendungsfälle ist ermöglicht und ein solches Momentenventil kann für Pumpen unterschiedlicher Größe und Leistung verwendet werden, ohne daß zusätzliche Anpassungsmaßnahmen erforderlich sind.The design and arrangement of the torque valve according to the invention in a flow control means that the torque valve can be attached to the hydraulic pump as a separate assembly and a driver pin of the pump actuator acts directly on the torque valve to change the preload of the measuring spring / measuring spring set depending on the flow rate setting. Since the torque characteristic is determined solely by the design of the characteristic of the measuring spring or the measuring spring set and the measuring spring is set directly via the driver pin, the preload of the measuring spring or the measuring spring set can be adjusted from outside by a stop in the torque valve by means of a handle. Due to the externally adjustable measuring spring or measuring spring set, any number of different torque characteristics can be preselected and also set or adjusted during operation, which is particularly advantageous when the pump torque is optimally adapted to the torque of the drive machine driving the pump. A quick adaptation to any application is possible and such a moment valve can be used for pumps of different sizes and capacities without additional adaptation measures being necessary.

In weiterer Ausbildung kann zweckmäßig der Anschlag im Momentenventil stirnseitig am Ventilgehäuse angeordnet und für den Austausch der Meßfeder/Meßfedersatzes lösbar sein.In a further embodiment, the stop in the torque valve can expediently be arranged on the end of the valve housing and be detachable for the exchange of the measuring spring / measuring spring set.

In zweckmäßiger Weiterbildung der Erfindung ist die Momentenregeleinrichtung auch als Summenregelung für zwei oder mehrere antriebsseitig mechanisch gekoppelte Hydropumpen geeignet, wenn erfindungsgemäß daß das Schließglied des Momen- tenventils jeder Pumpe von der Summe des Druckes in der betriebsdruck-Steuerleitung der einzelnen Pumpe und dem Druck in der betriebsdruckleitung der anderen Pumpe/Pumpen beaufschlagt ist und daß jedes Momentenventil die betriebsdruck-Steuerleitung seiner pumpe in Abhängigkeit vom Summenbetriebsdruck und der Vorspannung seiner Meßfeder mit dem drucklosen Ablauf verbindet. Dazu weisen die Schließglieder der Momentenventile mehrere Meßflächen auf, die parallel wirken und jeweils vom betriebsdruck einer der Pumpen beaufschlagt sind.In an expedient development of the invention, the torque control means is also suitable as total control for two or more drive side mechanically coupled hydraulic pumps, if according to the invention that the closing member of the momen - tenventils each pump from the sum of the pressure is applied in the operating pressure control line of the individual pump and the pressure in the operating pressure line of the other pump (s) and that each torque valve connects the operating pressure control line of its pump depending on the total operating pressure and the preload of its measuring spring with the unpressurized outlet. For this purpose, the closing elements of the torque valves have several measuring surfaces which act in parallel and are each acted upon by the operating pressure of one of the pumps.

Beispielsweise Ausführungsformen der Erfindung werden im folgenden anhand der beiliegenden Zeichnungen näher beschrieben. Es zeigen

  • Figur 1 schematisch eine erfindungsgemäße Regeleinrichtung für eine Hydropumpe,
  • Figur 2 schematisch im Schnitt und im Ausschnitt ein auf einer Hydropumpe angebrachtes Momentenventil gemäß der Erfindung,
  • Figur 3 schematisch die erfindungsgemäße Regeleinrichtung für zwei antriebsseitig gekoppelte Hydropumpen, und
  • Figur 4 schematisch im Ausschnitt und in vergrößerter Darstellung das Momentenventil mit einem Schließglied mit mehreren Meßflächen.
For example, embodiments of the invention are described in more detail below with reference to the accompanying drawings. Show it
  • FIG. 1 shows schematically an inventive control device for a hydraulic pump,
  • FIG. 2 schematically, in section and in detail, a torque valve according to the invention attached to a hydraulic pump,
  • Figure 3 shows schematically the control device according to the invention for two hydraulic pumps coupled on the drive side, and
  • Figure 4 shows schematically in detail and in an enlarged view the torque valve with a closing member with several measuring surfaces.

Die Hydropumpe 1 wird über die Welle 2 durch einen nichtdargestellten Antrieb angetrieben. Handelt es sich bei der Hydropumpe 1 beispielsweise um eine verstellbare Axialkolbenpumpe, besteht das Pumpenstellglied aus einem Schwenkglied 3, dessen Schwenkwinkel a dem Hubvolumen der Hydropumpe 1 proportional ist. Das nicht näher dargestellte Servostellgerät zur Einstellung des Schwenkwinkels a umfaßt eine Feder 4 und einen druckbeaufschlagbaren Stellkolben 5, wobei die Feder 4 die Hydropumpe 1 in Richtung maximalen Schwenkwinkel a, das heißt maximalen Fördervolumen einstellt. Ein Stellkolben 6 des Stellgerätes, der auch mit dem Kolben 5 funktionell vereinigt sein kann, übemimmt die Rücksteilfunktion in Richtung kleinerer Schwenkwinkel a. Seine Kolbenfläche ist wesentlich größer als die des Stellkolbens 5. Der auf den Kolben 6 wirkende Steuerdruck in der Leitung 7 wird über ein Steuerventil 8 und die Leitung 9 von der Förderdruckleitung 10 der Hydropumpe 1 abgenommen. Mit dem Steuerventil 8 in Reihe liegt ein übliches Druckbegrenzungsventil 11. Das Steuerventil 8 istals Druckwaage ausgebildet und einerseits vom Förderdruck beaufschlagt und andererseits von einem Steuerdruck in der betriebsdruck-Steuerleitung 12, welche den betriebsdruck der Hydropumpe 1 hinter einer den Steuerstrom begrenzenden Drossel 13 von der betriebsdruckleitung 14 nach einer gegebenenfalls verstellbaren Förderstromdrossel 15 abnimmt.The hydraulic pump 1 is driven via the shaft 2 by a drive, not shown. If the hydraulic pump 1 is, for example, an adjustable axial piston pump, the pump actuator consists of a swivel element 3, the swivel angle a of which is proportional to the stroke volume of the hydraulic pump 1. The servo actuator, not shown, for adjusting the swivel angle a comprises a spring 4 and a pressurizable actuating piston 5, the spring 4 adjusting the hydraulic pump 1 in the direction of the maximum swivel angle a, that is to say the maximum delivery volume. An actuating piston 6 of the actuating device, which can also be functionally combined with the piston 5, takes over the back part function in the direction of a smaller pivot angle a. Its piston area is significantly larger than that of the control piston 5. The control pressure acting on the piston 6 in the line 7 is removed via a control valve 8 and the line 9 from the delivery pressure line 10 of the hydraulic pump 1. A common pressure relief valve 11 is located in series with the control valve 8. The control valve 8 is designed as a pressure compensator and is acted upon on the one hand by the delivery pressure and on the other hand by a control pressure in the operating pressure control line 12, which controls the operating pressure of the hydraulic pump 1 behind a throttle 13 which limits the control flow operating pressure line 14 decreases after an optionally adjustable flow restrictor 15.

Ein Momentenventil 16 ist einerseits vom Druck in der Steuerleitung 12 beaufschlagt und andererseits von einer Meßfeder bzw. Meßfedersatz 17, dessen Vorspannung durch die Stellung des Kolben 6 bzw. des Pumpenstellgliedes 3 bestimmt ist. Das Momentenventil 16 kann die Steuerleitung 12 mit dem drucklosen Ablauf 18 verbinden.A moment valve 16 is acted upon on the one hand by the pressure in the control line 12 and on the other hand by a measuring spring or measuring spring set 17, the pretension of which is determined by the position of the piston 6 or the pump actuator 3. The torque valve 16 can connect the control line 12 to the unpressurized outlet 18.

Erreicht der Betriebsdruck in der Steuerleitung 12 den am Momentenventil 16 eingestellten Wert, so daß dieses beginnt zum Ablauf zu öffnen, entsteht über die Drossel 13 ein Druckgefälle am Steuerschieber des Steuerventiles 8. Der Steuerschieber wird in die Schaltposition 11 verschoben und versorgt den Kolben 6 mit Steuerdruck, so daß dieser bestrebt ist, das Stellglied 3 der Hydropumpe 1 in Richtung kleinerer Fördermengen zu verstellen. Dabei wird die Meßfeder 17 bzw. der Meßfedersatz des Momentenventiles 16 vorgespannt. Die Meßfedern bzw. der Meßfedersatz ist in ihrer Federcharakteristik so ausgebildet. daß je nach Vorspannung eine Hüllkurve in der theoretisch gewünschten Leistungshyperbel entsteht. Einem definierten betriebsdruck in der Leitung 10 entspricht ein vorgegebener Schwenkwinkel a. Die Fördermengeneinstellung der Hydropumpe 1 in dem Bereich, in welchem die Momentenregelung, das heißt das Momentenventil 16 noch nicht angesprochen hat, erfolgt in üblicher Weise über die Fördermengendrossel 15 und bedarf keiner besonderten Erläuterung.If the operating pressure in the control line 12 reaches the value set on the torque valve 16 so that it begins to open, a pressure drop occurs at the control slide of the control valve 8 via the throttle 13. The control slide is moved into the switching position 11 and supplies the piston 6 with Control pressure, so that it strives to adjust the actuator 3 of the hydraulic pump 1 in the direction of smaller flow rates. The measuring spring 17 or the measuring spring set of the torque valve 16 is biased. The measuring springs or the measuring spring set are designed in their spring characteristics. that, depending on the preload, an envelope is created in the theoretically desired power hyperbola. A defined swivel angle a corresponds to a defined operating pressure in line 10. The delivery rate setting of the hydraulic pump 1 in the area in which the torque control, that is to say the torque valve 16 has not yet responded, is carried out in the usual way via the delivery rate throttle 15 and requires no special explanation.

In Figur 2 ist eine Ausführungsform eines Momentenventiles 16 in seiner Zuordnung zu dem schwenkbaren Pumpenstellglied einer Schrägachsen-Axialkolbenpumpe dargestellt. Die Pumpe ist im einzelnen nicht näher erläutert. Das Schwenkbare Stellglied weist einen in das Momentenventil 16 ragenden Mitnehmerstift 20 auf. Das Momentenventil 16 ist bei der gezeigten Ausführungsform als in einem Ventilgehäuse 21 angeordnetes Sitzventil ausgebildet mit einem Ventilkegel 22 als Schließglied, welches von einem aus den Federn 23 und 24 gebildeten Meßfedersatz 17 beaufschlagt ist. Oer Ventilsitz für den Ventilkegel 22 ist an einem in dem Ventilgehäuse 21 verschiebbar angeordneten Ventilkörper 25 ausgebildet, an welchem der Mitnehmerstift 20 des Pumpenstellgliedes angreift. Oer Ventilkörper ist von einer Feder 26 beaufschlagt, welche im Ventilgehäuse 21 abgestützt ist und den Ventilkörper 25 formschlüssig mit dem Mitnehmerstift 20 in Eingriff hält. Die Feder 23 des Meßfedersatzes 17 ist an einem Anschlag 27 abgestützt und die Feder 24 an einer Stellschraube .28 in dem Anschlag 27.FIG. 2 shows an embodiment of a torque valve 16 in its assignment to the pivotable pump actuator of an inclined-axis axial piston pump. The pump is not explained in detail. The pivotable actuator has a driver pin 20 projecting into the torque valve 16. In the embodiment shown, the torque valve 16 is designed as a seat valve arranged in a valve housing 21 with a valve cone 22 as a closing element, which is acted upon by a measuring spring set 17 formed from the springs 23 and 24. The valve seat for the valve cone 22 is formed on a valve body 25 which is displaceably arranged in the valve housing 21 and on which the driver pin 20 of the pump actuator acts. The valve body is acted upon by a spring 26 which is supported in the valve housing 21 and holds the valve body 25 in positive engagement with the driver pin 20. The spring 23 of the measuring spring set 17 is supported on a stop 27 and the spring 24 on an adjusting screw .28 in the stop 27.

Der Anschlag 27 ist stirnseitig in das Ventilgehäuse 21 eingeschraubt. Durch die Drehstellung des Anschlages 27 ist die Vorspannung des Meßfedersatzes 17 und damit die Lage der gewünschten Momentenkennlinien sowie der Ansprechpunkt des Momentenventiles 16 einstellbar. Dazu weist der Anschlag 27 eine Handhabe 29 auf. Der verlauf der Momentenkennlinien bzw. der Federcharakteristik kann durch Veränderung der Vorspannung der Feder 24 mit Hilfe der Stellschraube 28 erfolgen.The stop 27 is screwed into the end of the valve housing 21. Due to the rotational position of the stop 27, the preload of the measuring spring set 17 and thus the position of the desired torque characteristics and the response point of the torque valve 16 can be adjusted. For this purpose, the stop 27 has a handle 29. The course of the torque characteristics or the spring characteristic can be done by changing the preload of the spring 24 with the help of the adjusting screw 28.

Der in der Betriebsdruck-Steuerleitung 12 anstehende Druck wirkt durch den Kanal 30 in dem Ventilkörper25 auf das Schließglied 22 gegen die Kraft des Meßfedersatzes 17. Die Weite des Ventilsitzes bestimmt dabei die für den Druck in der Leitung 12 wirksame Meßfläche am Schließglied 22. Übersteigt die durch den Druck in der Leitung 12 auf die Meßfläche ausgeübte Kraft die Vorspannkraft des Meßfedersatzes 17, hebt der ventilkegel des Schließgliedes 22 vom Ventilsitz im Ventilkörper 25 ab und öffnet die Steuerleitung 12 zum drucklosen Ablauf, gebildet durch den Innenraum 31 des fest mit der Hydropumpe verbundenen Ventilgehäuses 21, wobei der Innenraum 31 mit dem drucklosen Innenraum 32 der Hydropumpe in Verbindung steht.The pressure present in the operating pressure control line 12 acts through the channel 30 in the valve body25 on the closing member 22 against the force of the measuring spring set 17. The width of the valve seat determines the effective measuring area on the closing member 22 for the pressure in line 12. If the force exerted on the measuring surface by the pressure in line 12 exceeds the prestressing force of the measuring spring set 17, the valve cone of the closing member 22 lifts off the valve seat in the valve body 25 and opens the control line 12 to the unpressurized outlet, formed by the interior 31 of the valve housing 21 which is fixedly connected to the hydraulic pump, the interior 31 being connected to the unpressurized interior 32 of the hydraulic pump stands.

Durch die Bewegung des Pumpenstellgliedes in Richtung kleinerer Fördermengen bewegt der Mitnehmerstift 20 den Ventilkörper 25 in Figur 2 nach rechts gegen das Schließglied 22 und erhöht damit die Vorspannung des Federsatzes 17 entsprechend dem gewünschten Verlauf der Momentenkennlinie.Due to the movement of the pump actuator in the direction of smaller delivery quantities, the driving pin 20 moves the valve body 25 in FIG. 2 to the right against the closing member 22 and thus increases the preload of the spring set 17 in accordance with the desired course of the torque characteristic.

In Figur 3 ist die erfindungsgemäße Regeleinrichrtung als Summenmomemtenregelung für zwei Hydropumpen 33, 34 dargestellt, deren Antriebswellen direkt oder über ein entsprechendes Verteilergetriebe 35 (nur schematisch durch einen Strich angedeutet) von einer gemeinsamen nicht dargestellten Antriebsmaschine angetrieben werden. Die Regeleinrichtungen für die einzelnen Pumpen entsprechen der in Figur 1 dargestellten Regeleinrichtung. Gleiche Teile sind mit gleichen Bezugszeichen versehen und werden nicht nochmals erläutert. Lediglich die in Figur 1 mit 16 bezeichneten Momentenventile sind hier als Summenmomentenventile 36 ausgebildet und unterscheiden sich von dem Momentenventil 16 dadurch, daß das Schließglied 22 gemäß Figur 4 eine zusätzliche Meßfläche 37 aufweist. Auf diese Meßfläche 37 wirkt jeweils über eine Steuerleitung 38, 39 der Betriebsdruck der anderen Pumpe. Das Ansprechen, das heißt Öffnen der Momenteventile 36 für das Steuerdruckmittel in den Leitungen 12 zum drucklosen Ablauf erfolgt somit in Abhängigkeit von der Summe der Betriebsdrücke. Solche Regelungen sind zum Beispiel erforderlich, wenn zwei Hydropumpen von einer gemeinsamen Antriebswelle oder über ein Verteilergetriebe angetrieben werden und die Summe beider Aufnahmemomente der Pumpen das Antriebsmoment nicht überschreiten darf.In FIG. 3, the control device according to the invention is shown as a total torque control for two hydraulic pumps 33, 34, the drive shafts of which are driven directly or via a corresponding transfer gear 35 (only indicated schematically by a dash) by a common drive machine, not shown. The control devices for the individual pumps correspond to the control device shown in FIG. The same parts are provided with the same reference numerals and are not explained again. Only the torque valves denoted by 16 in FIG. 1 are designed here as total torque valves 36 and differ from the torque valve 16 in that the closing element 22 according to FIG. 4 has an additional measuring surface 37. The operating pressure of the other pump acts on this measuring surface 37 via a control line 38, 39. The response, that is to say the opening of the momentary valves 36 for the control pressure medium in the lines 12 for the unpressurized discharge, is thus dependent on the sum of the operating pressures. Such regulations are necessary, for example, if two hydraulic pumps are driven by a common drive shaft or via a transfer case and the sum of the two torques of the pumps must not exceed the drive torque.

Claims (6)

1. Output control device for an adjustable hydropump, having a hydraulic servomechanism for continuous adjustment of the pump output, in which the output setting is determined by the output pressure of the hydropump and the pressure in a working pressure control line, and in which the adjusting mechanism includes a spring (4) urging the pump control member in the direction of maximum output and at least one piston (6) acting on the pump control member in the direction of reduction in output, the piston face being exposed to the output pressure through a hydraulically operated control valve, or connected with the outlet, the control valve being operated by the pressure in the working pressure control line, wherein a torque valve (16, 36) is provided whose closure force is determined by a measuring spring or set of springs (17) effectively connected to the pump control member (3) and tensioned as a function of the output setting, and wherein the torque valve (16, 36) connects the working pressure control line (12) to the pressureless outlet (18) depending on the output pressure and the pressure in the working pressure control line (12) and the tension in the measuring spring (17), characterised in that the torque valve (16, 36) is fixed on to the hydropump (1) as a separate unit, and a follower pin (20) of the pump control member engages the torque valve (16, 36) to alter the tension in the measuring spring or set of springs (17), depending on the output setting, in that the torque valve (16) is in the form of a seat valve in which the valve cone constituting the closure member (22) is acted on by the measuring spring or set of springs (17), which is or are supported on the other side by an adjustable stop (27) in the valve housing (21), and wherein the valve seat is arranged in a displaceable valve body (25) which is engaged by the follower pin (20), and in that the stop (27) for the measuring spring or set of springs is adjustable from outside by means of a hand control (29).
2. Control device according to claim 1, characterised in that the pressure acting on the control valve (8) and the torque valve (16) or their closure members is received in the working pressure control line (12) as the pressure beyond a throttle (13) in the control line branching off from the working pressure line (14) of the pump (1), and an output throttle (15), which may be variable, is provided upstream of the branch in the control line (12).
3. Control device according to claim 1, characterised in that the valve body (25) is loaded by a spring that holds it closely up against the follower pin (20).
4. Control device according to claim 1, characterised in that the stop ( 2 7 ) is arranged on the front of the valve housing ( 21 ) and can be released to exchange the measuring spring or set of springs (17).
5. Control device according to any preceding claim as a combined control for two or more hyd- ropumps mechanically coupled on the drive side, characterised in that the closure member (22) of the torque valve of each pump (33, 34) is exposed to the sum of the pressure in the working pressure control line (12) of the individual pumps and the pressure in the working pressure line (14) of the other pump or pumps, and that each torque valve (36) connects the working pressure control line (12) of its pump with the pressureless outlet (18) depending on the combined working pressure and the tension in its measuring spring (17).
6. Control device according to claim 5, characterised in that the closure members of the torque valves have several measuring faces which act in parallel and are each exposed to the working pressure of one of the pumps.
EP84115198A 1983-12-14 1984-12-12 Feed controlling device for a variable hydropump Expired - Lifetime EP0149787B2 (en)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE8335902U DE8335902U1 (en) 1983-12-14 1983-12-14 Torque control device for an adjustable hydraulic pump
DE19833345264 DE3345264A1 (en) 1983-12-14 1983-12-14 TORQUE CONTROL UNIT FOR AN ADJUSTABLE HYDROPUMP
DE3345264 1983-12-14

Publications (4)

Publication Number Publication Date
EP0149787A2 EP0149787A2 (en) 1985-07-31
EP0149787A3 EP0149787A3 (en) 1985-08-21
EP0149787B1 EP0149787B1 (en) 1987-05-06
EP0149787B2 true EP0149787B2 (en) 1991-10-02

Family

ID=25816438

Family Applications (1)

Application Number Title Priority Date Filing Date
EP84115198A Expired - Lifetime EP0149787B2 (en) 1983-12-14 1984-12-12 Feed controlling device for a variable hydropump

Country Status (4)

Country Link
US (1) US4668171A (en)
EP (1) EP0149787B2 (en)
JP (1) JPS60147588A (en)
DE (2) DE8335902U1 (en)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19646687C1 (en) * 1996-10-31 1998-02-12 Brueninghaus Hydromatik Gmbh Power and moment regulator for several variable output hydraulic pumps
DE10001826C1 (en) * 2000-01-18 2001-09-20 Brueninghaus Hydromatik Gmbh Device for regulating the performance of an adjustable piston machine
US6324841B1 (en) 1996-10-31 2001-12-04 Brueninghaus Hydromatik Gmbh Power- and moment-regulating system for a plurality of hydraulic pumps

Families Citing this family (22)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3644769A1 (en) * 1986-12-30 1988-07-14 Brueninghaus Hydraulik Gmbh CONTROL DEVICE FOR AN ADJUSTABLE HYDROSTATIC MACHINE
DE3742111A1 (en) * 1987-04-02 1989-06-29 Brueninghaus Hydraulik Gmbh CONTROL DEVICE FOR AT LEAST TWO HYDROSTATIC MACHINES VARIABLE CONVEYORS OR CONNECTED TO A COMMON WORKING PRESSURE LINE. SWALLOWING VOLUME
DE3711050A1 (en) * 1987-04-02 1988-10-20 Brueninghaus Hydraulik Gmbh CONTROL DEVICE FOR AT LEAST TWO HYDROSTATIC MACHINES CONNECTED TO A COMMON WORKING PRESSURE LINE
DE3711053A1 (en) * 1987-04-02 1988-10-20 Brueninghaus Hydraulik Gmbh CONTROL DEVICE FOR AT LEAST TWO HYDROSTATIC MACHINES CONNECTED TO A COMMON WORKING PRESSURE LINE
JP2578371B2 (en) * 1989-09-22 1997-02-05 株式会社小松製作所 Displacement control device for variable displacement pump
DE4020325C2 (en) * 1990-06-26 1995-01-05 Hydrokraft Gmbh Control device for adjustable hydraulic pumps
DE4118869C2 (en) * 1991-06-07 1995-06-29 Hydromatik Gmbh Control device for controlling the displacement volume of several hydrostatic machines
DE4141108A1 (en) * 1991-12-13 1993-06-17 Putzmeister Maschf DEVICE FOR REGULATING THE OUTLET PRESSURE OF A PUMP
DE4202631C2 (en) * 1992-01-30 1995-07-06 Hydromatik Gmbh Axial piston machine, in particular hydraulic pump of the swash plate type or of the inclined axis type, the throughput volume of which can be adjusted by an adjusting device
DE4208925C1 (en) * 1992-03-19 1993-06-03 Hydromatik Gmbh, 7915 Elchingen, De
US5538401A (en) * 1994-07-05 1996-07-23 Denison Hydraulics Inc. Axial piston pump
KR100212645B1 (en) * 1994-09-30 1999-08-02 토니헬샴 Discharge flow rate control device of hydraulic pump
DE19517974A1 (en) * 1995-05-16 1996-11-21 Brueninghaus Hydromatik Gmbh Slidable hydraulic power or torque control device
JPH0986805A (en) * 1995-09-25 1997-03-31 Kandenko Co Ltd Cable drum brake
DE19742157C2 (en) 1997-09-24 1999-07-01 Brueninghaus Hydromatik Gmbh Control device for an adjustable hydraulic pump with several consumers
DE19831587C2 (en) * 1998-07-14 2000-06-15 Brueninghaus Hydromatik Gmbh Power control device for controlling the hydraulic power of a hydraulic pump
DE10341331B3 (en) * 2003-09-08 2005-05-25 Brueninghaus Hydromatik Gmbh Power control device
WO2008022672A1 (en) * 2006-08-21 2008-02-28 Joma-Hydromechanic Gmbh Feed pump
US8647075B2 (en) * 2009-03-18 2014-02-11 Eaton Corporation Control valve for a variable displacement pump
US9086143B2 (en) 2010-11-23 2015-07-21 Caterpillar Inc. Hydraulic fan circuit having energy recovery
DE102016123160A1 (en) * 2016-11-30 2018-05-30 Schwing Gmbh Large manipulator with quick folding and unfolding articulated mast
DE102017213458A1 (en) 2017-08-03 2019-02-07 Robert Bosch Gmbh Hydrostatic axial piston machine with power limitation

Family Cites Families (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR1318661A (en) * 1961-12-27 1963-02-22 Sciper Sa Safety device for positive displacement pumps
GB1126873A (en) * 1964-09-22 1968-09-11 Sperry Rand Corp Improvements in hydraulic supply and control systems
NL165340C (en) * 1968-05-09 1981-03-16 Philips Nv DEVICE FOR GENERATING STIMULATED INFRARED EMISSIONS WITH A WAVE LENGTH OF APPROXIMATELY 10.6 MU OF CONTAINERS FOR MAINTAINING AN ELECTRIC DISCHARGE IN A PARTICULAR GAS FLUID.
DE1921298B2 (en) * 1969-04-25 1973-08-23 Hydromatik Gmbh, 7900 Ulm DEVICE FOR REGULATING THE FLOW RATE OF ADJUSTABLE AXIAL PISTON PUMPS
DE1922269A1 (en) * 1969-04-29 1970-11-12 Bellows Valvair Kaemper Gmbh Total power controller
BE757640A (en) * 1969-10-16 1971-04-16 Borg Warner HYDRAULIC SYSTEMS, ESPECIALLY FOR THE REGULATION OF A VARIABLE FLOW PUMP
US3669570A (en) * 1970-03-09 1972-06-13 Mannesmann Meer Ag Power regulation for fluid machines
US3768928A (en) * 1971-06-01 1973-10-30 Borg Warner Pump control system
DE2141722A1 (en) * 1971-08-20 1973-03-01 Bosch Gmbh Robert PRESSURE REGULATOR FOR AN ADJUSTABLE PUMP
US3856436A (en) * 1972-12-18 1974-12-24 Sperry Rand Corp Power transmission
DD110684A1 (en) * 1974-03-20 1975-01-05
US3935707A (en) * 1974-07-22 1976-02-03 General Signal Corporation Hydraulic control system
US3941513A (en) * 1974-09-05 1976-03-02 Parker-Hannifin Corporation Variable displacement pump control assembly
DE2461897A1 (en) * 1974-12-31 1976-07-08 Bosch Gmbh Robert CONTROL DEVICE FOR A PUMP
DE2551088C2 (en) * 1975-11-14 1984-06-28 Mannesmann Rexroth GmbH, 8770 Lohr Device for volume and pressure control for variable displacement pumps
US4348159A (en) * 1980-01-07 1982-09-07 Rexnord Inc. Convertible pump servo-valve control
JPS57107407A (en) * 1980-12-25 1982-07-03 Daikin Ind Ltd Construction equipment such as power shovel
DE3213958A1 (en) * 1981-08-21 1983-03-03 Robert Bosch Gmbh, 7000 Stuttgart ELECTROHYDRAULIC ADJUSTMENT FOR A HYDROSTATIC MACHINE

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19646687C1 (en) * 1996-10-31 1998-02-12 Brueninghaus Hydromatik Gmbh Power and moment regulator for several variable output hydraulic pumps
US6324841B1 (en) 1996-10-31 2001-12-04 Brueninghaus Hydromatik Gmbh Power- and moment-regulating system for a plurality of hydraulic pumps
DE10001826C1 (en) * 2000-01-18 2001-09-20 Brueninghaus Hydromatik Gmbh Device for regulating the performance of an adjustable piston machine

Also Published As

Publication number Publication date
DE8335902U1 (en) 1987-06-04
US4668171A (en) 1987-05-26
EP0149787A3 (en) 1985-08-21
EP0149787A2 (en) 1985-07-31
EP0149787B1 (en) 1987-05-06
JPS60147588A (en) 1985-08-03
DE3345264A1 (en) 1985-06-27
JPH0526955B2 (en) 1993-04-19

Similar Documents

Publication Publication Date Title
EP0149787B2 (en) Feed controlling device for a variable hydropump
DE2343611C2 (en) Device for load-dependent control of a hydrostatic variable displacement pump
EP0826110B1 (en) Sliding hydraulic output and moment regulation device
DE2813486C2 (en) Control device for hydraulic pumps
DE2350390B2 (en)
EP0137185A2 (en) Hydraulic system with a variable-delivery pump and a priority valve
DE1916224B2 (en) Hydrostatic transmission
DE1653385B2 (en) Device for keeping the product of pressure and stroke volume constant in a positive displacement pump
DE2528094A1 (en) CONTROL SYSTEM FOR HYDROSTATIC TRANSMISSION
DE2321335C2 (en) Combined pressure and volume-dependent control for a drive device consisting of two hydrostatic gears
DE2321655A1 (en) HYDROSTATIC TRANSMISSION
DE2927627A1 (en) TRANSMISSION WITH HYDRAULIC CONTROL
EP0273214A2 (en) Controlling system for a hydrostatic machine
EP1502027B1 (en) Regulatory device comprising a threshold value control valve
DE3320047C2 (en)
DE69501497T2 (en) Control for an axial piston pump with variable stroke
EP1017942A1 (en) Regulating device for an adjustable hydraulic pump with several consumers
DE2322998C3 (en) Hydraulic adjusting device, in particular for a steering
DE4020325C2 (en) Control device for adjustable hydraulic pumps
DE19808127C2 (en) Power control device
DE3711050C2 (en)
EP0972939B1 (en) Power control for multiple hydropumps
DE1929645A1 (en) Device for setting the displacement volume in hydraulic fluid pumps or motors
EP0284989B1 (en) Regulator for at least two hydrostatic machines linked to a common pressure pipe
EP0954703B1 (en) Power- and moment-regulating system for a plurality of hydraulic pumps

Legal Events

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

Free format text: ORIGINAL CODE: 0009012

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Designated state(s): DE FR GB IT SE

AK Designated contracting states

Designated state(s): DE FR GB IT SE

17P Request for examination filed

Effective date: 19850711

17Q First examination report despatched

Effective date: 19860411

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT SE

ITF It: translation for a ep patent filed
ET Fr: translation filed
REF Corresponds to:

Ref document number: 3463555

Country of ref document: DE

Date of ref document: 19870611

PLBI Opposition filed

Free format text: ORIGINAL CODE: 0009260

26 Opposition filed

Opponent name: HYDROKRAFT GMBH

Effective date: 19880205

PUAH Patent maintained in amended form

Free format text: ORIGINAL CODE: 0009272

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

Free format text: STATUS: PATENT MAINTAINED AS AMENDED

27A Patent maintained in amended form

Effective date: 19911002

AK Designated contracting states

Kind code of ref document: B2

Designated state(s): DE FR GB IT SE

ITF It: translation for a ep patent filed
ET3 Fr: translation filed ** decision concerning opposition
ITTA It: last paid annual fee
EAL Se: european patent in force in sweden

Ref document number: 84115198.8

REG Reference to a national code

Ref country code: GB

Ref legal event code: IF02

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

Ref country code: GB

Payment date: 20031126

Year of fee payment: 20

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

Ref country code: SE

Payment date: 20031202

Year of fee payment: 20

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

Ref country code: DE

Payment date: 20031205

Year of fee payment: 20

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

Ref country code: FR

Payment date: 20031209

Year of fee payment: 20

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

Ref country code: GB

Free format text: LAPSE BECAUSE OF EXPIRATION OF PROTECTION

Effective date: 20041211

REG Reference to a national code

Ref country code: GB

Ref legal event code: PE20

EUG Se: european patent has lapsed
EUG Se: european patent has lapsed
PLAB Opposition data, opponent's data or that of the opponent's representative modified

Free format text: ORIGINAL CODE: 0009299OPPO