EP0086276B1 - Device for maintaining the product of the delivery pressure and delivery rate of an adjustable pump at a constant level - Google Patents

Device for maintaining the product of the delivery pressure and delivery rate of an adjustable pump at a constant level Download PDF

Info

Publication number
EP0086276B1
EP0086276B1 EP82112000A EP82112000A EP0086276B1 EP 0086276 B1 EP0086276 B1 EP 0086276B1 EP 82112000 A EP82112000 A EP 82112000A EP 82112000 A EP82112000 A EP 82112000A EP 0086276 B1 EP0086276 B1 EP 0086276B1
Authority
EP
European Patent Office
Prior art keywords
force
lever
spring
pump
piston
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
Application number
EP82112000A
Other languages
German (de)
French (fr)
Other versions
EP0086276A1 (en
Inventor
Gerhard Dipl.-Ing. Nonnenmacher
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.)
Robert Bosch GmbH
Original Assignee
Robert Bosch 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
Application filed by Robert Bosch GmbH filed Critical Robert Bosch GmbH
Publication of EP0086276A1 publication Critical patent/EP0086276A1/en
Application granted granted Critical
Publication of EP0086276B1 publication Critical patent/EP0086276B1/en
Expired 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
    • 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
    • F04—POSITIVE - DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS FOR LIQUIDS OR ELASTIC FLUIDS
    • F04B—POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS
    • F04B2201/00—Pump parameters
    • F04B2201/12—Parameters of driving or driven means
    • F04B2201/1203—Power on the axis

Definitions

  • the invention relates to a device according to the preamble of the main claim.
  • a known device has the disadvantage that its application is limited by the fact that it requires adaptation work for each type of pump and each desired product of pressure and volume, which causes undesirable costs.
  • this device for pumps with a small adjustment path is often not available (DE-A-2 362 093).
  • a hydrostatic converter with at least one hydraulic motor and at least one adjustable pump, which can be adjusted continuously by an actuator, has also become known, the characteristic curve representing the relationship between the delivery pressure and the displacement also has a hyperbolic part, which is determined by a torque regulator on the pump.
  • This is provided with a device for generating a variable auxiliary force, the size of which can be adjusted for the displacement of the hyperbolic part of the characteristic curve in the characteristic diagram of the hydraulic motor with the aid of the actuator for the pump.
  • the actuator is coupled to the operating lever of the drive machine for the converter.
  • This known device is somewhat complicated and in turn only suitable for a very specific purpose (DE-A-2 620 692).
  • the device according to the invention with the characterizing features of the main claim has the advantage that it is considerably more flexible, since different pump sizes and types can be operated with the same regulator with the exception of a spring and that it is also very well suited for pumps with a small adjustment range.
  • FIGS. 1 to 11 show in FIGS. 1 to 11 different embodiments of the device according to the invention in a schematic representation.
  • 10 is an adjustable pump, for example a radial piston pump, whose adjusting member 12, which determines the stroke of piston 11, is adjusted with the aid of two pressurized adjusting pistons 13, 14.
  • the actuating piston 13 has a substantially smaller area than the actuating piston 14.
  • the actuating piston 13 is always acted upon by the pressure prevailing in the delivery line 15 via a line 16.
  • a line 17 also branches off from the delivery line 15 and leads to a 3/3-way valve 18 with the switching positions I, 11, 111.
  • a line 19 leads from the directional control valve 18 to the bore 20 receiving the actuating piston 14.
  • a line 21 leads from the directional control valve 18 to the container 22, from which the pump 10 also sucks in pressure medium.
  • a compression spring 24 is arranged in the actuating piston 14, one end of which rests against the bottom of the actuating piston 14, while its other end always acts on the one slide side 18 ′ of the directional control valve 18.
  • the other side 18 "of the directional valve slide is articulated via an extension 25 to one end 26 of an angled, two-armed lever 27, on the other end 28 of which a spring 29 acts on a lever arm a which is always of the same length. It is also important that the spring 24 acting on the directional control valve 18 has largely linear characteristics.
  • the pivot point D of the lever 27 rests on a roller 31 which is arranged at the end of the piston rod 32 of a piston 33 which is slidably guided even in a pressurized cylinder 34.
  • the pressure chamber 35 of the cylinder 34 is always acted upon by the delivery pressure of the pump via a line 36 connected to the delivery line 15.
  • a compression spring 37 acts on the piston 33 against the liquid force. It is essential that the spring 37 has a largely linear characteristic.
  • the pivot point D forms two lever arms a and b on the lever 27.
  • the force of the spring 29 is denoted by F1 or second force, the force of the spring 24 by F2 or first force.
  • the control valve 18 is in the neutral position 11 when there is a balance of forces on the lever 27.
  • the piston 33 moves against the force of the spring 37, as a result of which the lever arm b becomes larger.
  • the moment from spring force F2 times lever arm b is greater than the always constant moment from spring force F1 times lever arm a, so that spring 24 can pivot lever 27 in such a way that directional valve 18 reaches its switching position 1.
  • Now pressure medium from the delivery line 15 can enter the bore 20 via the lines 17, 19 and move the actuating piston 14 to the left, whereupon the adjusting member 12 of the pump is set to a lower delivery rate. The result of this is that the spring 24 relaxes by moving the actuating piston 14 to the left.
  • the moment of spring force F1 and lever arm a now predominates, so that the lever 27 is now pivoted clockwise and the directional valve 18 returns to its neutral position. A new state of equilibrium has thus occurred.
  • the power or torque according to the invention ment controller thus converts via spring 24 with an approximately linear characteristic a path of actuating piston 14 that is at least approximately linearly proportional to the delivery volume of the pump into a force (spring 24).
  • the exemplary embodiment according to FIG. 2 is shown in simplified form compared to the previous one, ie the pump and the lines connected there are missing. The same parts are labeled with the same numbers.
  • the now stretched double-acting lever bears the designation 40.
  • the lever 40 counteracts this spring 41 in the same line of action as that of the spring 24. It is supported on a bearing 42 fixed to the housing. It is hereby achieved that no transverse forces act on the control slide 18 and the cylinder 34, as a result of which the adjustability to changes in force is improved.
  • the mode of operation is otherwise exactly the same as in the exemplary embodiment according to FIG. 1.
  • the lever for comparing forces is now designed with one arm and is designated 45 and is articulated on the piston rod 32 of the cylinder 34.
  • one end of a spiral spring 46 is fastened, the other end of which acts on the lever 45.
  • the spiral spring takes over the function of the spring 29, that is, it generates the counter torque to the torque from the force of the spring 24 times the lever arm b.
  • the mode of action is exactly the same as described above.
  • the exemplary embodiments according to FIGS. 5 to 7 again largely correspond to those described above, but with the following difference:
  • the pump is reset to a smaller delivery rate by actuating the actuating piston 14 - see FIG. 8 in this regard - in the exemplary embodiments according to FIGS. 5 to 7, it is just the other way round.
  • the pump is set to a larger delivery rate by acting on the actuating piston 14.
  • the spring 29 acts on the lever 27 in the opposite direction.
  • the eccentricity e is now opposite to that of the examples described above.
  • FIGS. 6 and 7 correspond to exemplary embodiments 4 and 3, the mode of operation results automatically from what has been described above and what has been said about exemplary embodiments 3 and 4, so that further discussions regarding the mode of operation are no longer necessary.
  • the pressure measuring element designed as a cylinder 34 is advantageously designed to be free of lateral forces in accordance with FIGS. 10 and 11.
  • the cylinder is pivotally attached at 60.
  • the reaction force of the lever 27 is supported on a part 61 fixed to the housing by means of at least one roller 31, preferably attached with the same axis, with the same or different diameter.
  • the roller 31 advantageously consists of three rollers that can move independently of one another.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Reciprocating Pumps (AREA)
  • Details And Applications Of Rotary Liquid Pumps (AREA)

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einer Einrichtung nach der Gattung des Hauptanspruchs. Eine derartige bekannte Einrichtung hat den Nachteil, dass ihre Einsatzmöglichkeit dadurch begrenzt ist, dass sie für jeden Pumpentyp und jedes gewünschte Produkt von Druck und Volumen Anpassarbeiten erfordert, was unerwünschte Kosten verursacht. Ausserdem ist die Einsatzmöglichkeit dieser Einrichtung für Pumpen mit kleinem Verstellweg oft nicht gegeben (DE-A-2 362 093).The invention relates to a device according to the preamble of the main claim. Such a known device has the disadvantage that its application is limited by the fact that it requires adaptation work for each type of pump and each desired product of pressure and volume, which causes undesirable costs. In addition, the use of this device for pumps with a small adjustment path is often not available (DE-A-2 362 093).

Es ist ferner ein stufenlos durch ein Stellorgan einstellbarer hydrostatischer Wandler mit mindestens einem Hydromotor und mindestens einer verstellbaren Pumpe bekanntgeworden, deren den Zusammenhang von Förderdruck und Hubvolumen darstellende Kennlinie ebenfalls einen hyperbolischen Teil besitzt, der durch einen Drehmomentenregler an der Pumpe bestimmt wird. Dieser ist zur Erzeugung einer variablen Hilfskraft mit einer Vorrichtung versehen, deren Grösse zwecks Verschiebung des hyperbolischen Teils der Kennlinie im Kennfeld des Hydromotors mit Hilfe des Stellorgans für die Pumpe einstellbar ist. Dabei ist das Stellorgan mit dem Bedienungshebel der Antriebsmaschine für den Wandler gekoppelt. Diese bekannte Einrichtung ist etwas kompliziert und wiederum nur für einen ganz bestimmten Zweck geeignet (DE-A-2 620 692).A hydrostatic converter with at least one hydraulic motor and at least one adjustable pump, which can be adjusted continuously by an actuator, has also become known, the characteristic curve representing the relationship between the delivery pressure and the displacement also has a hyperbolic part, which is determined by a torque regulator on the pump. This is provided with a device for generating a variable auxiliary force, the size of which can be adjusted for the displacement of the hyperbolic part of the characteristic curve in the characteristic diagram of the hydraulic motor with the aid of the actuator for the pump. The actuator is coupled to the operating lever of the drive machine for the converter. This known device is somewhat complicated and in turn only suitable for a very specific purpose (DE-A-2 620 692).

Vorteile der ErfindungAdvantages of the invention

Die erfindungsgemässe Einrichtung mit den kennzeichnenden Merkmalen des Hauptanspruchs hat demgegenüber den Vorteil, dass sie wesentlich flexibler ist, da verschiedene Pumpengrössen und -typen mit Ausnahme einer Feder mit demselben Regler bedient werden können und dass sie auch für Pumpen mit kleinem Verstellweg sehr gut geeignet ist.The device according to the invention with the characterizing features of the main claim has the advantage that it is considerably more flexible, since different pump sizes and types can be operated with the same regulator with the exception of a spring and that it is also very well suited for pumps with a small adjustment range.

Durch die in den Unteransprüchen aufgeführten Massnahmen sind Weiterbildungen der im Hauptanspruch angegebenen Merkmale möglich.The measures listed in the subclaims make it possible to develop the features specified in the main claim.

Zeichnungdrawing

Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert. Diese zeigen in den Fig. 1 bis 11 verschiedene Ausführungsformen der erfindungsgemässen Einrichtung in schematischer Darstellung.An embodiment of the invention is shown in the drawing and explained in more detail in the following description. These show in FIGS. 1 to 11 different embodiments of the device according to the invention in a schematic representation.

Beschreibung des ErfindungsbeispielsDescription of the invention example

In Fig. 1 ist mit 10 eine verstellbare Pumpe, beispielsweise eine Radialkolbenpumpe, bezeichnet, deren den Hub von Kolben 11 bestimmendes Verstellglied 12 mit Hilfe zweier druckbeaufschlagter Stellkolben 13, 14 eingestellt wird. Der Stellkolben 13 hat eine wesentlich kleinere Fläche als der Stellkolben 14. Der Stellkolben 13 ist stets von dem in der Förderleitung 15 herrschenden Druck über eine Leitung 16 beaufschlagt. Von der Förderleitung 15 zweigt ausserdem noch eine Leitung 17 ab, die zu einem 3/3-Wegeventil 18 mit den Schaltstellungen I, 11,111 führt. Vom Wegeventil 18 führt eine Leitung 19 zu der den Stellkolben 14 aufnehmenden Bohrung 20. Weiterhin führt vom Wegeventil 18 eine Leitung 21 zum Behälter 22, aus dem auch die Pumpe 10 Druckmittel ansaugt.In Fig. 1, 10 is an adjustable pump, for example a radial piston pump, whose adjusting member 12, which determines the stroke of piston 11, is adjusted with the aid of two pressurized adjusting pistons 13, 14. The actuating piston 13 has a substantially smaller area than the actuating piston 14. The actuating piston 13 is always acted upon by the pressure prevailing in the delivery line 15 via a line 16. A line 17 also branches off from the delivery line 15 and leads to a 3/3-way valve 18 with the switching positions I, 11, 111. A line 19 leads from the directional control valve 18 to the bore 20 receiving the actuating piston 14. Furthermore, a line 21 leads from the directional control valve 18 to the container 22, from which the pump 10 also sucks in pressure medium.

Im Stellkolben 14 ist eine Druckfeder 24 angeordnet, deren eines Ende am Boden des Stellkolbens 14 anliegt, während ihr anderes Ende stets auf die eine Schieberseite 18' des Wegeventils 18 einwirkt. Die andere Seite 18" des Wegeventilschiebers ist über einen Fortsatz 25 mit dem einen Ende 26 eines abgewinkelten, zweiarmigen Hebels 27 gelenkig verbunden, auf dessen anderes Ende 28 eine Feder 29 an einem stets gleich langen Hebelarm a einwirkt. Wesentlich ist auch noch, dass die auf das Wegeventil 18 einwirkende Feder 24 weitgehend lineare Charakteristik aufweist.A compression spring 24 is arranged in the actuating piston 14, one end of which rests against the bottom of the actuating piston 14, while its other end always acts on the one slide side 18 ′ of the directional control valve 18. The other side 18 "of the directional valve slide is articulated via an extension 25 to one end 26 of an angled, two-armed lever 27, on the other end 28 of which a spring 29 acts on a lever arm a which is always of the same length. It is also important that the spring 24 acting on the directional control valve 18 has largely linear characteristics.

Der Schwenkpunkt D des Hebels 27 liegt an einer Rolle 31 an, die am Ende der Kolbenstange 32 eines Kolbens 33 angeordnet ist, der selbst in einem druckbeaufschlagten Zylinder 34 gleitend geführt ist. Der Druckraum 35 des Zylinders 34 ist über eine mit der Förderleitung 15 in Verbindung stehende Leitung 36 stets vom Förderdruck der Pumpe beaufschlagt. Entgegen der Flüssigkeitskraft wirkt auf den Kolben 33 eine Druckfeder 37 ein. Wesentlich ist, dass die Feder 37 eine weitgehend lineare Charakteristik aufweist.The pivot point D of the lever 27 rests on a roller 31 which is arranged at the end of the piston rod 32 of a piston 33 which is slidably guided even in a pressurized cylinder 34. The pressure chamber 35 of the cylinder 34 is always acted upon by the delivery pressure of the pump via a line 36 connected to the delivery line 15. A compression spring 37 acts on the piston 33 against the liquid force. It is essential that the spring 37 has a largely linear characteristic.

Durch den Schwenkpunkt D werden am Hebel 27 zwei Hebelarme a und b gebildet. Die Kraft der Feder 29 ist mit F1 bzw. zweite Kraft bezeichnet, die Kraft der Feder 24 mit F2 bzw. erste Kraft.The pivot point D forms two lever arms a and b on the lever 27. The force of the spring 29 is denoted by F1 or second force, the force of the spring 24 by F2 or first force.

Das Steuerventil 18 befindet sich in Neutralstellung 11, wenn Kräftegleichgewicht am Hebel 27 herrscht. Bei nun ansteigendem Förderdruck bewegt sich der Kolben 33 entgegen der Kraft der Feder 37, wodurch der Hebelarm b grösser wird. Dadurch wird das Moment aus Federkraft F2 mal Hebelarm b grösser als das stets konstante Moment aus Federkraft F1 mal Hebelarm a, so dass die Feder 24 den Hebel 27 so verschwenken kann, dass das Wegeventil 18 in seine Schaltstellung 1 gelangt. Nunmehr kann Druckmittel aus der Förderleitung 15 über die Leitungen 17, 19 in die Bohrung 20 eindringen und den Stellkolben 14 nach links verschieben, worauf das Verstellglied 12 der Pumpe auf geringere Fördermenge eingestellt wird. Das hat zur Folge, dass sich durch das Verschieben des Stellkolbens 14 nach links die Feder 24 entspannt. Nunmehr überwiegt das Moment aus Federkraft Fl und Hebelarm a, so dass nun der Hebel 27 im Uhrzeigersinn verschwenkt wird und das Wegeventil 18 wieder in seine Neutralstellung gelangt. Damit ist ein neuer Gleichgewichtszustand eingetreten.The control valve 18 is in the neutral position 11 when there is a balance of forces on the lever 27. When the delivery pressure now rises, the piston 33 moves against the force of the spring 37, as a result of which the lever arm b becomes larger. As a result, the moment from spring force F2 times lever arm b is greater than the always constant moment from spring force F1 times lever arm a, so that spring 24 can pivot lever 27 in such a way that directional valve 18 reaches its switching position 1. Now pressure medium from the delivery line 15 can enter the bore 20 via the lines 17, 19 and move the actuating piston 14 to the left, whereupon the adjusting member 12 of the pump is set to a lower delivery rate. The result of this is that the spring 24 relaxes by moving the actuating piston 14 to the left. The moment of spring force F1 and lever arm a now predominates, so that the lever 27 is now pivoted clockwise and the directional valve 18 returns to its neutral position. A new state of equilibrium has thus occurred.

Fällt nun der Förderdruck der Pumpe, so schiebt die Feder 37 den Kolben 33 nach unten, wodurch der Hebelarm b kleiner wird. Damit überwiegt das Drehmoment aus Federkraft F1 mal Hebelarm a, so dass das Wegeventil in seine Schaltstellung 111 gebracht wird. Nunmehr kann Druckmittel aus der Bohrung 20 zum Behälter abfliessen, und der stets vom Förderdruck beaufschlagte Stellkolben 13 stellt die Pumpe auf grössere Fördermenge ein. Durch das Verschieben des Stellkolbens 14 in Richtung Steuerventil 18 wird die Feder 24 stärker gespannt, so dass das Wegeventil 18 wieder in Neutralstellung gelangt.If the delivery pressure of the pump falls, the spring 37 pushes the piston 33 down, as a result of which the lever arm b becomes smaller. The torque from spring force F1 times lever arm a thus predominates, so that the directional control valve is brought into its switching position 111. Pressure medium can now flow out of the bore 20 to the container, and the actuating piston 13, which is always acted upon by the delivery pressure, adjusts the pump to a larger delivery rate. By moving the actuating piston 14 in the direction of the control valve 18, the spring 24 is tensioned more so that the directional control valve 18 returns to the neutral position.

Der erfindungsgemässe Leistungs- bzw. Drehmomentregler wandelt also über die Feder 24 mit etwa linearer Charakteristik einen dem Fördervolumen der Pumpe mindestens näherungsweise linear proportionalen Weg des Stellkolbens 14 in eine Kraft (Feder 24) um. Die Länge des Hebelarms b, an dem die Kraft der Feder 24 angreift, ändert seine Länge linear proportional mit dem jeweiligen Arbeitsdruck der Pumpe. Durch diese Arbeitsweise erhält man eine genaue Hyperbelkennlinie über Förderdruck und Fördermenge.The power or torque according to the invention ment controller thus converts via spring 24 with an approximately linear characteristic a path of actuating piston 14 that is at least approximately linearly proportional to the delivery volume of the pump into a force (spring 24). The length of the lever arm b, on which the force of the spring 24 acts, changes its length linearly proportional to the respective working pressure of the pump. This way of working gives an exact hyperbolic characteristic curve over delivery pressure and delivery quantity.

Das Ausführungsbeispiel nach Fig. 2 ist gegenüber dem vorherigen vereinfacht dargestellt, das heisst Pumpe und dort angeschlossene Leitungen fehlen. Gleiche Teile sind mit denselben Ziffern bezeichnet. Der nun gestreckt ausgebildete doppeltwirkende Hebel trägt die Bezeichnung 40. Abweichend zum vorherigen Ausführungsbeispiel wirkt auf den Hebel 40 in derselben Wirkungslinie wie die der Feder 24 dieser eine Feder 41 entgegen. Sie stützt sich an einem gehäusefesten Lager 42 ab. Man erreicht hierdurch, dass auf den Steuerschieber 18 und den Zylinder 34 keine Querkräfte einwirken, wodurch die Einstellfähigkeit auf Kraftänderungen verbessert wird. Die Funktionsweise ist ansonsten genau dieselbe wie beim Ausführungsbeispiel nach Fig. 1.The exemplary embodiment according to FIG. 2 is shown in simplified form compared to the previous one, ie the pump and the lines connected there are missing. The same parts are labeled with the same numbers. The now stretched double-acting lever bears the designation 40. In contrast to the previous exemplary embodiment, the lever 40 counteracts this spring 41 in the same line of action as that of the spring 24. It is supported on a bearing 42 fixed to the housing. It is hereby achieved that no transverse forces act on the control slide 18 and the cylinder 34, as a result of which the adjustability to changes in force is improved. The mode of operation is otherwise exactly the same as in the exemplary embodiment according to FIG. 1.

Das Ausführungsbeispiel nach Fig. 3 weicht in seiner konstruktiven Gestaltung wesentlich von den beiden obigen Ausführungsbeispielen ab, ist im Prinzip seiner Wirkungsweise jedoch gleich. Der Hebel zum Kräftevergleich ist nun einarmig ausgebildet und mit 45 bezeichnet und ist an die Kolbenstange 32 des Zylinders 34 angelenkt. An der Kolbenstange 32 ist das eine Ende einer Spiralfeder 46 befestigt, deren anderes Ende auf den Hebel 45 einwirkt. Die Spiralfeder übernimmt die Funktion der Feder 29, das heisst sie erzeugt das Gegendrehmoment zum Drehmoment aus der Kraft der Feder 24 mal dem Hebelarm b. Die Wirkungsweise ist prinzipiell wieder genau dieselbe wie oben beschrieben.3 differs significantly in its constructive design from the above two exemplary embodiments, but is basically the same in principle in its mode of operation. The lever for comparing forces is now designed with one arm and is designated 45 and is articulated on the piston rod 32 of the cylinder 34. On the piston rod 32, one end of a spiral spring 46 is fastened, the other end of which acts on the lever 45. The spiral spring takes over the function of the spring 29, that is, it generates the counter torque to the torque from the force of the spring 24 times the lever arm b. In principle, the mode of action is exactly the same as described above.

Beim Ausführungsbeispiel nach der Fig. 4 - das im übrigen weitestgehend demjenigen nach der Fig. 2 entspricht - ist es möglich, das gewünschte Drehmoment bzw. die gewünschte Leistung einzustellen. Dies gelingt mit Hilfe eines zweiten zweiarmigen Hebels 50, der etwa parallel zum Hebel 40 verläuft. Der Hebel 50 ist um den Schwenkpunkt D' verschwenkbar. An seiner einen Seite ist das eine Ende einer der Feder 29 entsprechenden Feder 51 angelenkt, deren anderes Ende am oberen Ende des Hebels 40 angreift. Am anderen Ende des Hebels 50 und auf der entgegengesetzten Seite der Feder 41 ist eine Stellschraube 52 vorgesehen, mit deren Hilfe die Neigung des Hebels 50 verändert werden kann und damit die Vorspannung der Federn 24 und 41. Durch Verdrehen der Stellschraube 52 werden die Ansprechkräfte auf das Ventil 18 verändert, woraus sich eine Änderung der Leistungs- bzw. Drehmomenthyperbel aus Förderdruck mal Fördervolumen ergibt.In the exemplary embodiment according to FIG. 4 - which otherwise largely corresponds to that according to FIG. 2 - it is possible to set the desired torque or the desired output. This is achieved with the aid of a second two-armed lever 50, which runs approximately parallel to lever 40. The lever 50 is pivotable about the pivot point D '. On one side is articulated one end of a spring 51 corresponding to the spring 29, the other end of which engages the upper end of the lever 40. At the other end of the lever 50 and on the opposite side of the spring 41, an adjusting screw 52 is provided, by means of which the inclination of the lever 50 can be changed and thus the pretension of the springs 24 and 41. By turning the adjusting screw 52, the response forces are on the valve 18 changes, which results in a change in the power or torque hyperbola from the delivery pressure times the delivery volume.

Die Ausführungsbeispiele nach den Fig. 5 bis 7 entsprechen wiederum weitestgehend den zuvor beschriebenen, jedoch mit folgendem Unterschied: Bei den Ausführungsbeispielen nach den Fig. 1 bis 4 wird die Pumpe auf kleinere Fördermenge durch Beaufschlagen des Stellkolbens 14 zurückgestellt - siehe hierzu Fig. 8 - bei den Ausführungsbeispielen nach den Fig. 5 bis 7 ist es gerade umgekehrt. Hier wird durch Beaufschlagung des Stellkolbens 14 die Pumpe auf grössere Fördermenge eingestellt. Dadurch ergibt sich lediglich folgende Veränderung bei diesen Ausführungsbeispielen: Die Feder 29 wirkt in der entgegengesetzten Richtung auf den Hebel 27 ein. Die Exzentrizität e liegt jetzt entgegengesetzt wie bei den zuvor beschriebenen Beispielen.The exemplary embodiments according to FIGS. 5 to 7 again largely correspond to those described above, but with the following difference: In the exemplary embodiments according to FIGS. 1 to 4, the pump is reset to a smaller delivery rate by actuating the actuating piston 14 - see FIG. 8 in this regard - in the exemplary embodiments according to FIGS. 5 to 7, it is just the other way round. Here, the pump is set to a larger delivery rate by acting on the actuating piston 14. This results in only the following change in these exemplary embodiments: The spring 29 acts on the lever 27 in the opposite direction. The eccentricity e is now opposite to that of the examples described above.

Herrscht beim Ausführungsbeisiel nach 5 Gleichgewicht am Hebel 27 und steigt der Förderdruck nun an, so bewegt sich der Kolben 33 im Zylinder 34 nach oben, wodurch der Hebelarm b vergrössert wird. Dadurch vergrössert sich auch das Drehmoment aus der Differenz der Kräfte der Federn 24 und 41 mal Hebelarm b. Das Gegenmoment aus Federkraft 29 mal Hebelarm a wird überwunden, und der Steuerschieber 18 wird in Schaltstellung 111 gebracht. Damit kann Druckmittel aus der Bohrung 20 zum Behälter 22 abfliessen. Der stets vom Förderdruck beaufschlagte Stellkolben 13 stellt die Pumpe auf kleinere Fördermenge ein. Sinkt der Druck, so wird der Kolben 13 durch die Feder 37 wieder nach unten vorgeschoben, so dass der Hebelarm b kleiner wird. Das Drehmoment aus Federkraft 29 mal Hebelarm a überwiegt wieder, der Steuerschieber 18 wird in Neutralstellung gebracht.If there is equilibrium on the lever 27 in the exemplary embodiment after 5 and the delivery pressure now rises, the piston 33 moves upward in the cylinder 34, as a result of which the lever arm b is enlarged. This also increases the torque from the difference in the forces of the springs 24 and 41 times lever arm b. The counter moment from spring force 29 times lever arm a is overcome and the control slide 18 is brought into switch position 111. Pressure fluid can thus flow out of the bore 20 to the container 22. The actuating piston 13, which is always acted upon by the delivery pressure, adjusts the pump to a smaller delivery rate. If the pressure drops, the piston 13 is pushed downwards again by the spring 37, so that the lever arm b becomes smaller. The torque from spring force 29 times lever arm a predominates again, the control slide 18 is brought into the neutral position.

Fällt der Druck in der Förderleitung weiter, so schiebt der Kolben 33 den Schwenkpunkt D nach unten, der Hebelarm b wird verkleinert, und es überwiegt das Drehmoment aus Federkraft 29 mal Hebelarm a. Nun wird das Steuerventil in Schaltstellung 1 gebracht, und Druckmittel kann aus der Förderleitung über die Leitung 19 in die Bohrung 20 eindringen und die Pumpe auf grössere Fördermenge einstellen. Dies geschieht so lange, bis wieder Gleichgewicht hergestellt ist.If the pressure in the delivery line continues to drop, the piston 33 pushes the pivot point D downward, the lever arm b is reduced, and the torque from spring force 29 times outweighs lever arm a. Now the control valve is brought into switch position 1, and pressure medium can enter the bore 20 from the delivery line via line 19 and adjust the pump to a larger delivery rate. This continues until equilibrium is restored.

Die Ausführungsbeispiele nach Fig. 6 und 7 entsprechen den Ausführungsbeispielen 4 und 3, die Funktionsweise ergibt sich aus dem oben Beschriebenen bzw. dem zu den Ausführungsbeispielen 3 und 4 Gesagten von selbst, so dass weitere Erörterungen bezüglich der Funktionsweise nicht mehr notwendig sind.The exemplary embodiments according to FIGS. 6 and 7 correspond to exemplary embodiments 4 and 3, the mode of operation results automatically from what has been described above and what has been said about exemplary embodiments 3 and 4, so that further discussions regarding the mode of operation are no longer necessary.

Was die Federn betrifft, so wäre noch folgendes zu sagen: Bei gleicher Federrate der Federn 51 und 41 bei den Ausführungsbeispielen nach den Fig. 4 und 6 wird der Einstellhebel mittig gelagert, anderenfalls wird das Lager so weit aus der Mitte verlegt, dass sich die Hebelarme der Federn umgekehrt proportional zu ihrer Federrate verhalten.As for the springs, the following would still be said: With the same spring rate of the springs 51 and 41 in the exemplary embodiments according to FIGS. 4 and 6, the adjusting lever is mounted in the center, otherwise the bearing is moved so far from the center that the Lever arms of the springs behave inversely proportional to their spring rate.

Das als Zylinder 34 ausgebildete Druckmessglied wird entsprechend den Fig. 10 und 11 vorteilhafterweise querkraftfrei ausgeführt. Zu diesem Zweck ist der Zylinder bei 60 schwenkbar befestigt. Die Reaktionskraft des Hebels 27 wird über wenigstens eine - vorzugsweise achsgleich angebrachte - Rolle 31 mit gleichem oder abweichendem Durchmesser an einem gehäusefesten Teil 61 abgestützt. Vorteilhafterweise besteht die Rolle 31 aus drei unabhängig voneinander beweglichen Rollen.The pressure measuring element designed as a cylinder 34 is advantageously designed to be free of lateral forces in accordance with FIGS. 10 and 11. For this purpose the cylinder is pivotally attached at 60. The reaction force of the lever 27 is supported on a part 61 fixed to the housing by means of at least one roller 31, preferably attached with the same axis, with the same or different diameter. The roller 31 advantageously consists of three rollers that can move independently of one another.

Claims (9)

1. Device for maintaining constant the product of the feed pressure and the feed volume of an adjustable pump having a single-acting or a double-acting lever, at which a balancing of forces takes place between a first force, which is applied by at least one spring (24) having an approximately linear characteristic, the pre-tension of which corresponds to a displacement which is in approximate linear proportion to the feed volume of the pump, and a second force, with a control valve (18) being actuated when the forces are unbalanced, which control valve (18) controls a regulating piston (14), acting onto the adjusting member (12) of the pump, until the feed volume of the regulating piston (14) is corrected in such a way that the second force re-establishes the state the equilibrium, with the length of the lever arm (b) changing in linear proportion to the particular working pressure of the pump, characterised in that the spring (24) forming the first force is supported on the one hand at the regulating piston (14) setting the adjusting member of the pump, and on the other hand at the control valve (18), and that the control valve acts directly onto the lever.
2. Device according to Claim 1, characterised in that the second force is produced by a spring (29, 46).
3. Device according to Claim 1 or 2, characterised in that the centre of gravity (D) of the lever is predetermined by a cylinder (34) which is pressurised by the feed pressure of the pump.
4. Device according to Claim 3, characterised in that the lever (27, 40, 45) fits against a roller (31) which is arranged on the piston rod (32) of the pressurised piston (33), onto which acts a spring (37) against the feed pressure.
5. Device according to one of Claims 1 to 4, characterised in that the lever of a double-arm design is straight or bent and the two forces act on its end points.
6. Device according to one of Claims 1 to 4, characterised in that the lever is of a single-arm design and the second force (counter torque) is produced by a helical spring (46) which is articulated on the piston rod of the pressurised piston (33).
7. Device according to one of Claims 1 to 6, characterised in that the second force is variable, especially by the spring (51) which forms the second force being supported at a second, double-arm lever (50) which, in the area of action of the first force, sits against an adjusting screw.
8. Device according to one of Claims 1 to 7, characterised in that a third force (41) acts on the double-arm lever in the direction of action of the first force, but in opposite sense.
9. Device according to Claims 1, 2, 4, 5 and 6, characterised in that the lever arm (a) on which acts the second force is always constant.
EP82112000A 1982-01-14 1982-12-24 Device for maintaining the product of the delivery pressure and delivery rate of an adjustable pump at a constant level Expired EP0086276B1 (en)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE3200867 1982-01-14
DE3200867 1982-01-14
DE19823207961 DE3207961A1 (en) 1982-01-14 1982-03-05 DEVICE FOR KEEPING THE PRODUCT OF DELIVERY PRESSURE AND DELIVERY VOLUME OF AN ADJUSTABLE PUMP
DE3207961 1982-03-05

Publications (2)

Publication Number Publication Date
EP0086276A1 EP0086276A1 (en) 1983-08-24
EP0086276B1 true EP0086276B1 (en) 1986-04-02

Family

ID=25798858

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82112000A Expired EP0086276B1 (en) 1982-01-14 1982-12-24 Device for maintaining the product of the delivery pressure and delivery rate of an adjustable pump at a constant level

Country Status (3)

Country Link
US (1) US4496290A (en)
EP (1) EP0086276B1 (en)
DE (2) DE3207961A1 (en)

Families Citing this family (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6131675A (en) * 1984-07-24 1986-02-14 Nippon Denso Co Ltd Variable capacity radial plunger pump
US6623250B2 (en) * 2000-02-17 2003-09-23 Goodrich Pump And Engine Control Systems, Inc. Fuel metering unit
US6962485B2 (en) * 2003-04-14 2005-11-08 Goodrich Pump And Engine Control Systems, Inc. Constant bypass flow controller for a variable displacement pump
US6916158B2 (en) * 2003-04-30 2005-07-12 Actuant Corporation Radial piston pump
US6996969B2 (en) * 2003-09-09 2006-02-14 Goodrich Pump & Engine Control Systems, Inc. Multi-mode shutdown system for a fuel metering unit
US20050100447A1 (en) * 2003-11-11 2005-05-12 Desai Mihir C. Flow control system for a gas turbine engine
US20080189085A1 (en) * 2004-07-29 2008-08-07 Can Technologies, Inc. System and method for optimizing animal production
US8123492B2 (en) * 2004-09-20 2012-02-28 Magna Powertrain Inc. Speed-related control mechanism for a pump and control method

Family Cites Families (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1425756A1 (en) * 1962-12-01 1969-04-10 Conen Dipl Ing Helmut Power regulator for a hydrostatic drive
US3504493A (en) * 1968-08-16 1970-04-07 Gen Motors Corp Hydraulic unit and control linkage with overload control
DE2362093A1 (en) * 1973-12-14 1975-06-19 Bosch Gmbh Robert Adjustable pump regulating installation - is to keep pressure and volume constant with pressure acting on a regulating lever
DE2419460A1 (en) * 1974-04-23 1975-11-06 Bosch Gmbh Robert Radial piston pump regulator - has opposite displacement ring a counter piston subjected to discharge pressure
DE2531492C2 (en) * 1975-07-15 1982-09-16 Robert Bosch Gmbh, 7000 Stuttgart Adjustable hydrostatic pump
DE2620692A1 (en) * 1976-05-07 1977-11-17 Volvo Hydraulikfabrik Gmbh HYDROSTATIC CONVERTER
DE2734933A1 (en) * 1977-08-03 1979-02-15 Linde Ag CONTROL DEVICE FOR AN AXIAL PISTON PUMP
DE2930139A1 (en) * 1979-07-25 1981-02-12 Linde Ag CONTROL DEVICE FOR A HYDROSTATIC TRANSMISSION OR A PISTON PUMP
DE2942403A1 (en) * 1979-10-19 1981-04-30 Linde Ag, 6200 Wiesbaden Volume control for hydraulic pump - has mechanical linkage to give hyperbolic relationship between discharge pressure and volume

Also Published As

Publication number Publication date
DE3207961A1 (en) 1983-07-21
DE3270327D1 (en) 1986-05-07
EP0086276A1 (en) 1983-08-24
US4496290A (en) 1985-01-29

Similar Documents

Publication Publication Date Title
EP0149787B2 (en) Feed controlling device for a variable hydropump
DE1528550C3 (en) Hydrostatic transmission with a pump and several hydraulic motors, each connectable via a directional valve, as well as a servo actuator
DE1653385C3 (en) Device for keeping the product of pressure and stroke volume constant in a positive displacement pump
DE2049884A1 (en) Hydraulic system
DE2910611A1 (en) HYDRAULIC SYSTEM
DE3709504C2 (en) Valve device
EP0086276B1 (en) Device for maintaining the product of the delivery pressure and delivery rate of an adjustable pump at a constant level
DE2551492A1 (en) CONTROL DEVICE FOR HYDRAULIC MACHINERY
DE2612270A1 (en) Swash plate pump regulating arrangement - has rotating housing and several cylinders with adjustable power stroke systems
DE2658241C2 (en) Device for limiting load control of hydraulic variable displacement pumps
EP1502027B1 (en) Regulatory device comprising a threshold value control valve
DE1528530C3 (en) Hydraulic pressure control device for variable displacement pumps
DE1911695C3 (en) Power controller with pressure cut-off for hydraulic pumps or motors of the axial piston swashplate design
EP0091569B1 (en) Output regulator for a hydrostatic pump
CH667496A5 (en) ADJUSTING DEVICE FOR THE DISPLACEMENT VOLUME OF A DISPLACEMENT MACHINE.
DE2362093A1 (en) Adjustable pump regulating installation - is to keep pressure and volume constant with pressure acting on a regulating lever
EP0093916A1 (en) Control apparatus for a variable displacement pump
DE2655966A1 (en) HYDRAULIC CONTROL DEVICE WITH ONE CONTROL PUMP
DE3034115A1 (en) PERFORMANCE CONTROLLER
DE2337481C2 (en) Sequence control device for an adjustable pump
CH615250A5 (en) Pressure controller for an adjustable hydropump
DE2206788A1 (en) ADJUSTABLE HYDRO PUMP WITH PRESSURE REGULATION
DE1267092B (en) Power regulator for piston pumps and motors
DE2810062A1 (en) Hydrostatic piston pump regulator - has servo piston with different end surface areas and piston transverse valve
DE2121267A1 (en) Variable displacement pump with adjustment device

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

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

17P Request for examination filed

Effective date: 19821224

AK Designated contracting states

Designated state(s): DE FR GB SE

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 SE

ET Fr: translation filed
REF Corresponds to:

Ref document number: 3270327

Country of ref document: DE

Date of ref document: 19860507

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

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

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Effective date: 19891225

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

Ref country code: FR

Payment date: 19891229

Year of fee payment: 8

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

Ref country code: GB

Payment date: 19891231

Year of fee payment: 8

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

Ref country code: DE

Payment date: 19900226

Year of fee payment: 8

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

Ref country code: GB

Effective date: 19901224

GBPC Gb: european patent ceased through non-payment of renewal fee
PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19910830

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

Ref country code: DE

Effective date: 19910903

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

EUG Se: european patent has lapsed

Ref document number: 82112000.3

Effective date: 19900829