EP0503260A1 - Device for a hydrostatic pump delivery control - Google Patents

Device for a hydrostatic pump delivery control Download PDF

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Publication number
EP0503260A1
EP0503260A1 EP92101590A EP92101590A EP0503260A1 EP 0503260 A1 EP0503260 A1 EP 0503260A1 EP 92101590 A EP92101590 A EP 92101590A EP 92101590 A EP92101590 A EP 92101590A EP 0503260 A1 EP0503260 A1 EP 0503260A1
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EP
European Patent Office
Prior art keywords
pump
control
spring
pressure
slide
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.)
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Application number
EP92101590A
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German (de)
French (fr)
Inventor
Volkmar Dipl.-Ing. Leutner
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Robert Bosch GmbH
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Robert Bosch GmbH
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Publication date
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP0503260A1 publication Critical patent/EP0503260A1/en
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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
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205—Systems with pumps
    • F15B2211/2053—Type of pump
    • F15B2211/20546—Type of pump variable capacity
    • F15B2211/20553—Type of pump variable capacity with pilot circuit, e.g. for controlling a swash plate
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/255—Flow control functions

Definitions

  • the invention relates to a device for controlling the delivery rate of a hydrostatic pump according to the preamble of the main claim.
  • a device for controlling the delivery rate of a hydrostatic pump according to the preamble of the main claim.
  • Such a device is known from the publication "Hydraulics in theory and practice” by Bosch, 1983 edition, page 68.
  • This device has the disadvantage that the temperature of the pressure medium is not taken into account in any way. So it can happen that the differential pressure control swings the pump out completely, even if this results in inadmissible operating conditions on the suction side up to a total breakdown of the suction process.
  • the device according to the invention for regulating the delivery rate of a hydrostatic pump has the advantage, in contrast, that as the oil temperature falls, an increasingly smaller pump adjustment corresponds to a certain opening of the measuring orifice in the limit, the pump is no longer adjusted regardless of the opening condition of the measuring orifice.
  • FIG. 1 An embodiment of the device according to the invention is shown in the following description and drawing.
  • the latter shows a device for controlling the delivery rate of an adjustable pump in a partially schematic representation or a control valve in partial section.
  • 10 denotes an adjustable pump which sucks oil out of a container 12 via a suction line 11.
  • the actuator 10A of the pump for example the swash plate of an axial piston pump, is adjusted with the aid of two adjusting pistons 13, 14.
  • the actuating piston 14 has a substantially smaller area than the actuating piston 13 and is acted upon by the delivery line 15 of the pump via a control line 16.
  • An adjustable diaphragm 16 is arranged in the delivery line 15.
  • a control line 17 branches off from the delivery line 15 in front of the orifice 16 and opens to the housing 18 of a control valve 19 for controlling the delivery rate of the pump. From a point behind the orifice 16, a control line 20 extends from the delivery line, which leads to a pressure pilot valve 21 and from which a control line 22 branches, which likewise opens out on the housing 18. A control line 24 continues from the control valve 19, which opens at the large actuating piston 13. In addition, an outflow line 25 leads from the control valve and leads to the container 12.
  • a slide bore 26 is formed in the housing 18 of the control valve, in which a control slide 27 is slidably guided.
  • the slide bore 26 opens at the upper part of the housing 18 into a pressure chamber 28, in which a control spring 29 is arranged, which acts on one end face of the control slide via a spring plate 30.
  • the pressure chamber 28 is connected to the control line 22 via an intermediate bore 31, i. H. the pressure behind the orifice 16 prevails in the pressure chamber 28.
  • an orifice 33 is also arranged in the control line 20, but is only effective when the pilot valve 21 is open.
  • the annular groove 34 is connected to the control line 17 via a housing bore 37, the annular groove 35 via a housing bore 38 to the control line 24 and the annular groove 36 via a housing bore 39 to the outflow line 25.
  • Control collars 40, 41, 42 are on the circumference of the control slide formed, inside the control slide there is an almost continuous blind bore 43, from the two opposite ends of which transverse bores 44, 45 lead to the outside. This creates a connection from the housing bore 37 to a pressure chamber 46 on the lower side of the control slide.
  • a displaceable disk 48 is arranged in the pressure chamber 46, against which the lower end face of the control slide bears, and a prestressed compression spring 49 acts on the underside of this disk, which bears against a spring plate 50, which in turn bears against the plunger 51 of a solenoid 52 .
  • a temperature sensor 54 Arranged near the mouth of the suction line in the container is a temperature sensor 54 designed as a PTC thermistor, from which an electrical line 55 leads to the solenoid 52 and an electrical line 56 to a current source 57 with a constant voltage, from which from an electrical line 58 also leads to the other pole of the solenoid 52. From the described device it can be seen that the two springs 29, 49 counteract each other on the control slide 27. The bias of the regulator spring 29 is constant at a certain setting by an adjusting screw 60, while the bias of the spring 49 can be changed by the solenoid 52.
  • the small actuating piston 14 is always acted upon by the pressure in the delivery line 15 of the pump upstream of the throttle, and this pressure also continues via the control line 17 and the housing bore 37 to the annular groove 34, penetrates through the transverse bore 44 into the blind bore 43 on the control slide valve and also propagates through the transverse bore 45 into the pressure chamber 46.
  • the throttle 16 there is a pressure drop of approximately 10 bar, which is caused by the prestressing of the control spring 29.
  • the pressure behind the orifice 16 prevails, which propagates there via the control lines 20, 22 and the housing bore 31. From this it can be seen that the pressure difference at the orifice 16 prevails at the control slide 27, and the differential force of the two springs 29 , 49.
  • the control slide controls with its control collars the connection again from the annular groove 34 via the annular groove 35 and the control line 24 to the large actuating piston 13 or the connection thereof via the annular groove 35 to the annular groove 36 and from there via the control line 25 to the container 12.
  • the preload given by the control spring 29 or the consumer pressure set the control slide so that it adjusts the actuator 12 of the pump in such a way that the pressure difference at the orifice 16 remains constant. In this way, a delivery rate of the pump 10 predetermined by the control spring 29 is achieved.
  • the preload of the spring 49 is dependent on the temperature at the temperature sensor 54. As the temperature of the oil falls, the resistance of the temperature sensor drops, the magnetic current increases and with it the magnetic force and the preload of the compression spring 49; the resulting spring force drops. Because this also reduces the pressure drop across the measuring throttle 16, the assignment of the measuring throttle opening to the setting of the pump actuator 12 changes in the sense that, as the oil temperature drops, an increasingly smaller pump adjustment corresponds to a certain measuring throttle opening until, in the limit case, the pump is independent of The opening state of the diaphragm 16 is no longer adjusted at all, ie the pump no longer delivers. In this way, a reduction in the delivery volume flow of the pump with falling oil temperature is achieved.

Abstract

The device for controlling the delivery rate of an adjustable pump (10) has a control element (12) which can be adjusted by means of two actuating pistons (13, 14). One of the actuating pistons is controlled by means of a control valve (19), the control slide (27) of which is acted upon by the pressure differential of an orifice (16) arranged in the feedline (15). The control slide is also acted upon by a control spring (29) which slide acts against a spring (49), the bias of which is determined by a lifting magnet (52). The lifting magnet is influenced by a temperature sensor (54) which is arranged in the vicinity of the intake point in the reservoir (12) of the pump. In this way the pump is returned as the oil cools. <IMAGE>

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einer Einrichtung zur Regelung der Fördermenge einer hydrostatischen Pumpe nach der Gattung des Hauptanspruchs. Eine derartige Einrichtung ist bekannt aus der Druckschrift "Hydraulik in Theorie und Praxis" von Bosch, Ausgabe 1983, Seite 68. Diese Einrichtung hat den Nachteil, daß die Temperatur des Druckmediums in keiner Weise berücksichtigt wird. So kann es geschehen, daß durch die Differenzdruckregelung die Pumpe voll ausgeschwenkt wird, auch wenn bei niedriger Mediumtemperatur dadurch auf der Saugseite unzulässige Betriebszustände bis hin zum totalen Zusammenbruch des Saugvorgangs eintreten.The invention relates to a device for controlling the delivery rate of a hydrostatic pump according to the preamble of the main claim. Such a device is known from the publication "Hydraulics in theory and practice" by Bosch, 1983 edition, page 68. This device has the disadvantage that the temperature of the pressure medium is not taken into account in any way. So it can happen that the differential pressure control swings the pump out completely, even if this results in inadmissible operating conditions on the suction side up to a total breakdown of the suction process.

Vorteile der ErfindungAdvantages of the invention

Die erfindungsgemäße Einrichtung zur Regelung der Fördermenge einer hydrostatischen Pumpe hat demgegenüber den Vorteil, daß bei fallender Öltemperatur zu einer bestimmten Öffnung der Meßblende eine immer kleiner werdernde Pumpenverstellung korrespondiert, bis im Grenzfall die Pumpe unabhängig vom Öffnungszustand der Meßblende überhaupt nicht mehr verstellt wird.The device according to the invention for regulating the delivery rate of a hydrostatic pump has the advantage, in contrast, that as the oil temperature falls, an increasingly smaller pump adjustment corresponds to a certain opening of the measuring orifice in the limit, the pump is no longer adjusted regardless of the opening condition of the measuring orifice.

Weitere Vorteile der Erfindung ergeben sich aus den Unteransprüchen.Further advantages of the invention emerge from the subclaims.

Ein Ausführungsbeispiel der erfindungsgemäßen Einrichtung ist in der nachfolgenden Beschreibung und Zeichnung wiedergegeben. Letztere zeigt eine Einrichtung zur Regelung der Fördermenge einer verstellbaren Pumpe in teils schematischer Darstellung bzw. ein Regelventil im Teilschnitt.An embodiment of the device according to the invention is shown in the following description and drawing. The latter shows a device for controlling the delivery rate of an adjustable pump in a partially schematic representation or a control valve in partial section.

Beschreibung des AusführungsbeispielsDescription of the embodiment

In Figur 1 ist mit 10 eine verstellbare Pumpe bezeichnet, die über eine Saugleitung 11 Öl aus einem Behälter 12 ansaugt. Das Stellglied 10A der Pumpe, beispielsweise die Schrägscheibe einer Axialkolbenpumpe, wird mit Hilf zweier Stellkolben 13, 14 eingestellt. Der Stellkolben 14 hat eine wesentlich kleinere Fläche als der Stellkolben 13 und wird von der Förderleitung 15 der Pumpe her über eine Steuerleitung 16 beaufschlagt. In der Förderleitung 15 ist eine verstellbare Blende 16 angeordnet.In FIG. 1, 10 denotes an adjustable pump which sucks oil out of a container 12 via a suction line 11. The actuator 10A of the pump, for example the swash plate of an axial piston pump, is adjusted with the aid of two adjusting pistons 13, 14. The actuating piston 14 has a substantially smaller area than the actuating piston 13 and is acted upon by the delivery line 15 of the pump via a control line 16. An adjustable diaphragm 16 is arranged in the delivery line 15.

Von der Förderleitung 15 zweigt vor der Blende 16 eine Steuerleitung 17 ab, die zum Gehäuse 18 eines Regelventils 19 für die Steuerung der Fördermenge der Pumpe mündet. Von einer Stelle hinter der Blende 16 geht von der Förderleitung eine Steuerleitung 20 aus, die zu einem Druck-Vorsteuerventil 21 führt und von der eine Steuerleitung 22 abzweigt, die ebenfalls am Gehäuse 18 mündet. Vom Steuerventil 19 geht weiterhin eine Steuerleitung 24 aus, die am großen Stellkolben 13 mündet. Außerdem geht vom Regelventil noch eine Abströmleitung 25 aus, die zum Behälter 12 führt.A control line 17 branches off from the delivery line 15 in front of the orifice 16 and opens to the housing 18 of a control valve 19 for controlling the delivery rate of the pump. From a point behind the orifice 16, a control line 20 extends from the delivery line, which leads to a pressure pilot valve 21 and from which a control line 22 branches, which likewise opens out on the housing 18. A control line 24 continues from the control valve 19, which opens at the large actuating piston 13. In addition, an outflow line 25 leads from the control valve and leads to the container 12.

Im Gehäuse 18 des Regelventils ist eine Schieberbohrung 26 ausgebildet, in welcher ein Regelschieber 27 gleitend geführt ist. Die Schieberbohrung 26 mündet am oberen Teil des Gehäuses 18 in einen Druckraum 28, in welchem eine Regelfeder 29 angeordnet ist, die über einen Federteller 30 auf die eine Stirnseite des Regelschiebers einwirkt. Der Druckraum 28 steht über eine Zwischenbohrung 31 mit der Steuerleitung 22 in Verbindung, d. h. im Druckraum 28 herrscht der Druck hinter der Blende 16. Dazu ist ergänzend zu sagen, daß auch in der Steuerleitung 20 noch eine Blende 33 angeordnet ist, die aber nur wirksam ist, wenn das Vorsteuerventil 21 geöffnet ist.A slide bore 26 is formed in the housing 18 of the control valve, in which a control slide 27 is slidably guided. The slide bore 26 opens at the upper part of the housing 18 into a pressure chamber 28, in which a control spring 29 is arranged, which acts on one end face of the control slide via a spring plate 30. The pressure chamber 28 is connected to the control line 22 via an intermediate bore 31, i. H. the pressure behind the orifice 16 prevails in the pressure chamber 28. In addition, it must be said that an orifice 33 is also arranged in the control line 20, but is only effective when the pilot valve 21 is open.

An der Schieberbohrung 26 sind drei hintereinanderliegende Ringnuten 34, 35, 36 ausgebildet. Die Ringnut 34 steht über eine Gehäusebohrung 37 mit der Steuerleitung 17 in Verbindung, die Ringnut 35 über eine Gehäusebohrung 38 mit der Steuerleitung 24 und die Ringnut 36 über eine Gehäusebohrung 39 mit der Abströmleitung 25. Am Umfang des Regelschiebers sind Steuerbunde 40, 41, 42 ausgebildet, im Inneren des Regelschiebers befindet sich eine fast durchgehende Sackbohrung 43, von deren beiden entgegengesetzten Enden Querbohrungen 44, 45 nach außen führen. Damit entsteht Verbindung von der Gehäusebohrung 37 zu einem Druckraum 46 an der unteren Seite des Regelschiebers. Im Druckraum 46 ist eine verschiebbare Scheibe 48 angeordnet, an die sich die untere Stirnseite des Regelschiebers anlegt und wobei auf die Unterseite dieser Scheibe eine vorgespannte Druckfeder 49 einwirkt, die sich an einen Federteller 50 anlegt, der selbst wiederum am Stößel 51 eines Hubmagneten 52 anliegt.Three ring grooves 34, 35, 36 lying one behind the other are formed on the slide bore 26. The annular groove 34 is connected to the control line 17 via a housing bore 37, the annular groove 35 via a housing bore 38 to the control line 24 and the annular groove 36 via a housing bore 39 to the outflow line 25. Control collars 40, 41, 42 are on the circumference of the control slide formed, inside the control slide there is an almost continuous blind bore 43, from the two opposite ends of which transverse bores 44, 45 lead to the outside. This creates a connection from the housing bore 37 to a pressure chamber 46 on the lower side of the control slide. A displaceable disk 48 is arranged in the pressure chamber 46, against which the lower end face of the control slide bears, and a prestressed compression spring 49 acts on the underside of this disk, which bears against a spring plate 50, which in turn bears against the plunger 51 of a solenoid 52 .

Nahe der Mündung der Saugleitung im Behälter ist ein als Kaltleiter ausgebildeter Temperaturfühler 54 angeordnet, von dem eine elektrische Leitung 55 zum Hubmagneten 52 führt sowie eine elektrische Leitung 56 zu einer Stromquelle 57 mit konstanter Spannung, von der aus eine elektrische Leitung 58 auch zum anderen Pol des Hubmagneten 52 führt. Aus der beschriebenen Einrichtung ist zu erkennen, daß am Regelschieber 27 die beiden Federn 29, 49 einander entgegenwirken. Die Vorspannung der Reglerfeder 29 ist bei einer bestimmten Einstellung durch eine Einstellschraube 60 konstant, während die Vorspannung der Feder 49 durch den Hubmagneten 52 veränderbar ist.Arranged near the mouth of the suction line in the container is a temperature sensor 54 designed as a PTC thermistor, from which an electrical line 55 leads to the solenoid 52 and an electrical line 56 to a current source 57 with a constant voltage, from which from an electrical line 58 also leads to the other pole of the solenoid 52. From the described device it can be seen that the two springs 29, 49 counteract each other on the control slide 27. The bias of the regulator spring 29 is constant at a certain setting by an adjusting screw 60, while the bias of the spring 49 can be changed by the solenoid 52.

Der kleine Stellkolben 14 ist stets vom Druck in der Förderleitung 15 der Pumpe vor der Drossel beaufschlagt, und dieser Druck setzt sich auch über die Steuerleitung 17 und die Gehäusebohrung 37 zur Ringnut 34 fort, dringt über die Querbohrung 44 in die Sackbohrung 43 am Regelschieber ein und pflanzt sich auch über die Querbohrung 45 in den Druckraum 46 fort. An der Drossel 16 ergibt sich ein Druckgefälle von etwa 10 bar, das durch die Vorspannung der Regelfeder 29 bedingt ist. Im Druckraum 29 herrscht der Druck hinter der Blende 16, der sich dorthin fortpflanzt über die Steuerleitungen 20, 22 sowie die Gehäusebohrung 31. Daraus ist zu erkennen, daß am Regelschieber 27 die Druckdifferenz an der Blende 16 herrscht, sowie die Differenzkraft der beiden Federn 29, 49. Der Regelschieber steuert mit seinen Steuerbunden die Verbindung wieder von der Ringnut 34 über die Ringnut 35 und die Steuerleitung 24 zum großen Stellkolben 13 bzw. die Verbindung von diesem über die Ringnut 35 zur Ringnut 36 und von dort über die Steuerleitung 25 zum Behälter 12. Die durch die Regelfeder 29 vorgegebene Vorspannung bzw. der Verbraucherdruck stellen den Regelschieber so ein, daß er das Stellglied 12 der Pumpe derart einstellt, daß die Druckdifferenz an der Blende 16 konstant bleibt. Auf diese Weise erreicht man eine durch die Regelfeder 29 vorgegebene Fördermenge der Pumpe 10.The small actuating piston 14 is always acted upon by the pressure in the delivery line 15 of the pump upstream of the throttle, and this pressure also continues via the control line 17 and the housing bore 37 to the annular groove 34, penetrates through the transverse bore 44 into the blind bore 43 on the control slide valve and also propagates through the transverse bore 45 into the pressure chamber 46. At the throttle 16 there is a pressure drop of approximately 10 bar, which is caused by the prestressing of the control spring 29. In the pressure chamber 29, the pressure behind the orifice 16 prevails, which propagates there via the control lines 20, 22 and the housing bore 31. From this it can be seen that the pressure difference at the orifice 16 prevails at the control slide 27, and the differential force of the two springs 29 , 49. The control slide controls with its control collars the connection again from the annular groove 34 via the annular groove 35 and the control line 24 to the large actuating piston 13 or the connection thereof via the annular groove 35 to the annular groove 36 and from there via the control line 25 to the container 12. The preload given by the control spring 29 or the consumer pressure set the control slide so that it adjusts the actuator 12 of the pump in such a way that the pressure difference at the orifice 16 remains constant. In this way, a delivery rate of the pump 10 predetermined by the control spring 29 is achieved.

Die Vorspannung der Feder 49 ist abhängig von der Temperatur am Temperaturfühler 54. Mit fallender Temperatur des Öls sinkt der Widerstand des Temperaturfühlers, der Magnetstrom steigt und mit ihm die Magnetkraft und die Vorspannung der Druckfeder 49; die resultierende Federkraft sinkt. Weil dadurch auch das an der Meßdrossel 16 liegende Druckgefälle kleiner wird, verändert sich die Zuordnung von Meßdrosselöffnung zu Einstellung des Pumpenstellglieds 12 in dem Sinne, das bei fallender Öltemperatur zu einer bestimmten Meßdrosselöffnung eine immer kleiner werdende Pumpenverstellung korrespondiert, bis im Grenzfall die Pumpe unabhängig vom Öffnungszustand der Blende 16 überhaupt nicht mehr verstellt wird, d. h. die Pumpe nicht mehr fördert. Auf diese Weise erreicht man eine Reduzierung des Fördervolumenstromes der Pumpe mit sinkender Öltemperatur.The preload of the spring 49 is dependent on the temperature at the temperature sensor 54. As the temperature of the oil falls, the resistance of the temperature sensor drops, the magnetic current increases and with it the magnetic force and the preload of the compression spring 49; the resulting spring force drops. Because this also reduces the pressure drop across the measuring throttle 16, the assignment of the measuring throttle opening to the setting of the pump actuator 12 changes in the sense that, as the oil temperature drops, an increasingly smaller pump adjustment corresponds to a certain measuring throttle opening until, in the limit case, the pump is independent of The opening state of the diaphragm 16 is no longer adjusted at all, ie the pump no longer delivers. In this way, a reduction in the delivery volume flow of the pump with falling oil temperature is achieved.

Ist ein bestimmter, durch das Druck-Vorsteuerventil 21 vorgegebener Förderdruck erreicht und öffnet dieses, so wird die Pumpe in bekannter Weise zurückgeregelt, bis der vorgegebene Förderdruck wieder erreicht ist. Dieser Vorgang ist bekannt.If a certain delivery pressure predetermined by the pressure pilot valve 21 is reached and opens it, the pump is regulated back in a known manner until the predetermined delivery pressure is reached again. This process is known.

Claims (3)

Einrichtung zur Regelung der Fördermenge, gegebenenfalls auch des Förderdrucks einer verstellbaren, eine relativ stark viskose Flüssigkeit wie Öl förderne hydrostatische Pumpe (10), deren Stellglied (10a) mit Hilfe wenigstens eines Stellkolbens (13) entgegen einer Gegenkraft einstellbar ist, dessen Stellung durch ein Regelventil (19) gesteuert wird, an dessen Regelschieber (27) die Druckdifferenz einer in der Pumpenförderleitung (15) angeordneten Meßdrossel oder Blende (16) wirksam ist und auf den auch von der Seite des niedrigeren Druckes her eine Regelfeder (29) einwirkt, dadurch gekennzeichnet, daß auf den Regelschieber (27) entgegen der Kraft der Regelfeder (29) eine zweite Feder (49) einwirkt, deren Vorspannung mit Hilfe eines Hubmagneten (52) veränderbar ist, der von einem in der Nähe der Saugstelle der Pumpe angeordneten Temperaturfühler (54) beeinflußt ist.Device for regulating the delivery rate, possibly also the delivery pressure of an adjustable hydrostatic pump (10) which delivers a relatively highly viscous liquid such as oil, the actuator (10a) of which can be adjusted with the aid of at least one adjusting piston (13) against a counterforce, the position of which can be adjusted by a Control valve (19) is controlled, on the control slide (27) the pressure difference of a measuring throttle or orifice (16) arranged in the pump delivery line (15) is effective and on which a control spring (29) also acts from the side of the lower pressure, thereby characterized in that, against the force of the control spring (29), a second spring (49) acts on the control slide (27), the pretension of which can be changed with the aid of a lifting magnet (52) which is actuated by a temperature sensor () located near the suction point of the pump ( 54) is influenced. Einrichtung nach Anspruch 1, dadurch gekennzeichnet, daß der Elektromagnet ein Hubmagnet ist und in Reihe mit dem als Kaltleiter ausgebildeten Temperaturfühler (54) an einer Stromquelle (57) mit konstanter Spannung liegt.Device according to Claim 1, characterized in that the electromagnet is a lifting magnet and is connected in series with the temperature sensor (54) designed as a PTC thermistor to a current source (57) with a constant voltage. Einrichtung nach Anspruch 1 und/oder 2, dadurch gekennzeichnet, daß auf das Stellglied (12) der Pumpe (10) einander entgegenwirkend zwei Stellkolben (13, 14) einwirken, von denen der eine (14) eine wesentlich kleinere druckbeaufschlagte Fläche hat und stets von der Hochdruckseite der Pumpe her beaufschlagt ist.Device according to claim 1 and / or 2, characterized in that two actuating pistons (13, 14) act counter to one another on the actuator (12) of the pump (10), one of which (14) has a substantially smaller pressurized surface and always from the high pressure side of the pump.
EP92101590A 1991-03-13 1992-01-31 Device for a hydrostatic pump delivery control Withdrawn EP0503260A1 (en)

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Application Number Priority Date Filing Date Title
DE19914107977 DE4107977C2 (en) 1991-03-13 1991-03-13 Device for regulating the delivery rate of a hydrostatic pump
DE4107977 1991-03-13

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EP0503260A1 true EP0503260A1 (en) 1992-09-16

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Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE102006004311B4 (en) * 2006-01-31 2011-07-21 ZF Lenksysteme GmbH, 73527 Hydraulic system with a flow control valve
DE102013216395B4 (en) * 2013-08-19 2019-01-17 Danfoss Power Solutions a.s. CONTROL DEVICE FOR HYDRAULIC ADJUSTING PUMPS AND ADJUSTING PUMP WITH A CONTROL DEVICE

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3637327A (en) * 1969-11-24 1972-01-25 Borg Warner Pump
US4189921A (en) * 1976-07-02 1980-02-26 Eaton Corporation Hydraulic controller
DE2952083A1 (en) * 1979-12-22 1981-06-25 Robert Bosch Gmbh, 7000 Stuttgart Control system for variable hydraulic pump - has output throttle and control valve permitting independent volume and pressure control
US4373869A (en) * 1980-08-22 1983-02-15 The Cessna Aircraft Company Warm-up valve in a variable displacement system
GB2123988A (en) * 1981-03-06 1984-02-08 Sundstrand Corp Viscosity compensating circuit
DE3506335A1 (en) * 1985-02-22 1986-08-28 Mannesmann Rexroth GmbH, 8770 Lohr SAFETY CIRCUIT FOR A HYDRAULIC SYSTEM

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE7501056U (en) * 1975-01-16 1976-07-22 Robert Bosch Gmbh, 7000 Stuttgart CONTROL DEVICE FOR A PUMP
DE3016609A1 (en) * 1980-04-30 1981-11-05 G.L. Rexroth Gmbh, 8770 Lohr Radial vane type pump - has throughput controlled by positioning valve energised by signal from discharge flow meter

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3637327A (en) * 1969-11-24 1972-01-25 Borg Warner Pump
US4189921A (en) * 1976-07-02 1980-02-26 Eaton Corporation Hydraulic controller
DE2952083A1 (en) * 1979-12-22 1981-06-25 Robert Bosch Gmbh, 7000 Stuttgart Control system for variable hydraulic pump - has output throttle and control valve permitting independent volume and pressure control
US4373869A (en) * 1980-08-22 1983-02-15 The Cessna Aircraft Company Warm-up valve in a variable displacement system
GB2123988A (en) * 1981-03-06 1984-02-08 Sundstrand Corp Viscosity compensating circuit
DE3506335A1 (en) * 1985-02-22 1986-08-28 Mannesmann Rexroth GmbH, 8770 Lohr SAFETY CIRCUIT FOR A HYDRAULIC SYSTEM

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DE4107977C2 (en) 1999-05-12
DE4107977A1 (en) 1992-09-17

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