EP0081703B1 - Electro-hydraulic actuator - Google Patents

Electro-hydraulic actuator Download PDF

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Publication number
EP0081703B1
EP0081703B1 EP82110794A EP82110794A EP0081703B1 EP 0081703 B1 EP0081703 B1 EP 0081703B1 EP 82110794 A EP82110794 A EP 82110794A EP 82110794 A EP82110794 A EP 82110794A EP 0081703 B1 EP0081703 B1 EP 0081703B1
Authority
EP
European Patent Office
Prior art keywords
throttle
pressure
pump
valve
chamber
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
EP82110794A
Other languages
German (de)
French (fr)
Other versions
EP0081703A1 (en
Inventor
Egon Dipl.-Ing. Lechner
Siegfried Mayer
Dieter Dipl.-Ing. Weigle
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 EP0081703A1 publication Critical patent/EP0081703A1/en
Application granted granted Critical
Publication of EP0081703B1 publication Critical patent/EP0081703B1/en
Expired legal-status Critical Current

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Classifications

    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B13/00—Details of servomotor systems ; Valves for servomotor systems
    • F15B13/02—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors
    • F15B13/04—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor
    • F15B13/0401—Valve members; Fluid interconnections therefor
    • F15B13/0402—Valve members; Fluid interconnections therefor for linearly sliding valves, e.g. spool valves
    • 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
    • F15B7/00—Systems in which the movement produced is definitely related to the output of a volumetric pump; Telemotors
    • F15B7/005—With rotary or crank input
    • F15B7/006—Rotary pump input

Definitions

  • the invention relates to an actuator according to the preamble of the main claim.
  • the reversible pump delivers pressure medium to a hydraulic motor either via one or the other pressure line.
  • the two pressure lines are connected by a line in which a throttle is located.
  • the speed of the hydraulic motor can be influenced by opening the throttle to a greater or lesser extent (FR-A-2009 929).
  • a pump is also driven by an electric motor, which acts on an actuating piston which is displaceable against the force of a spring.
  • the throttle can be used to branch off part of the pressure medium delivered by the pump and thus control the feed speed of the actuating piston (DE-C-841094).
  • a hydraulic speed controller has become known in which a pump sucks pressure medium from a container and conveys it via a series throttle to an actuating piston which actuates the throttle element of an internal combustion engine via a crank mechanism.
  • An adjustable throttle is in turn connected in parallel to the pump, via which a more or less large portion of the pump delivery flow is returned to the container. In this way, speed control of the actuating piston is also possible (US-A-4 218 884).
  • FIG. 1 shows an electrohydraulic actuator in a schematic representation
  • FIG. 2 shows a second, modified exemplary embodiment.
  • 10 denotes a direct current motor which drives a reversible hydrostatic pump 11, in particular a gear pump.
  • a control slide 17 is guided, which is loaded on both sides by springs 18 and 19 and centered.
  • a line 20 is connected to the pressure chamber 14, which leads to a container 21 and in which an adjustable throttle 22 is arranged.
  • a line 24 is also connected to the pressure chamber 15, which also leads to the container and in which an adjustable throttle 25 is also arranged.
  • the adjusting members 27 and 28 of the two throttles 22, 25 are connected by a coupling member 29 and can be pivoted about a point 30 such that they are adjusted in opposite directions.
  • a central annular groove 32 is formed on the control slide 17, through which a consumer connection A or B can be connected to a line 33 leading to the container 21.
  • Lines 35, 36 are connected to lines 12, 13, which lead to container 21 and in each of which a check valve 37, 38 is connected, which can open in the direction from the container to lines 12 and 13, respectively.
  • FIG. 2 differs from that of Figure 1 only in that the lines 35, 36 are omitted.
  • the pump 11 and the directional control valve 17 operate in a closed circuit.
  • the throttles 22, 25 can be used to draw pressure medium from the container 21.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Reciprocating Pumps (AREA)
  • Actuator (AREA)

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einem Stellantrieb nach der Gattung des Hauptanspruchs. Bei einem derartigen bekannten Stellantrieb fördert die reversible pumpe entweder uber die eine oder die andere Druckleitung Druckmittel zu einem Hydromotor. Die beiden Druckleitungen sind durch eine Leitung verbunden, in der sich eine Drossel befindet. Durch mehr oder weniger starkes Offnen der Drossel kann die Drehzahl des Hydromotors be-einflußt werden (FR-A- 2009 929).The invention relates to an actuator according to the preamble of the main claim. In such a known actuator, the reversible pump delivers pressure medium to a hydraulic motor either via one or the other pressure line. The two pressure lines are connected by a line in which a throttle is located. The speed of the hydraulic motor can be influenced by opening the throttle to a greater or lesser extent (FR-A-2009 929).

Bei einem anderen ähnlichen Stellantrieb wird ebenfalls von einem Elektromotor eine pumpe angetrieben, die einen Stellkolben beaufschlagt, der entgegen der Kraft einer Feder verschiebbar ist. Durch eine parallel geschaltete, verstellbare. Drossel kann ein Teil des von der pumpe geförderten Druckmittels abgezweigt und damit die Vorschubgeschwindigkeit des Stellkolbens gesteuert werden (DE-C-841094).In another similar actuator, a pump is also driven by an electric motor, which acts on an actuating piston which is displaceable against the force of a spring. Through a parallel, adjustable. The throttle can be used to branch off part of the pressure medium delivered by the pump and thus control the feed speed of the actuating piston (DE-C-841094).

Weiterhin ist ein hydraulischer Geschwindigkeitsregler bekannt geworden, bei dem eine pumpe Druckmittel aus einem Behälter ansaugt und dieses über eine in Serie geschaltete Drossel zu einem Stellkolben fördert, der über einen Kurbeltrieb das Drosselorgan einer Brennkraftmaschine betätigt. Parallel an die Pumpe ist wiederum eine verstellbare Drossel geschaltet, über die ein mehr oder weniger großer Anteil des pumpenförderstroms zum Behälter zurückgeführt wird. Auf diese Weise ist ebenfalls eine Geschwindigkeitssteuerung des Stellkolbens möglich (US-A-4 218 884).Furthermore, a hydraulic speed controller has become known in which a pump sucks pressure medium from a container and conveys it via a series throttle to an actuating piston which actuates the throttle element of an internal combustion engine via a crank mechanism. An adjustable throttle is in turn connected in parallel to the pump, via which a more or less large portion of the pump delivery flow is returned to the container. In this way, speed control of the actuating piston is also possible (US-A-4 218 884).

Aufgabetask

Es ist eine Aufgabe der Erfindung, einen elektrohydraulischen Stellantrieb nach dem Oberbegriff des Anspruchs 1 zu schaffen, der unmittelbar zum Betätigen eines Ventils geeignet ist und mit dem es möglich ist, mit Hilfe der Drehzahländerung des Elektromotors das Ventil feinfühlig einzustellen, insbesondere von einer entfernten Stelle aus.It is an object of the invention to provide an electrohydraulic actuator according to the preamble of claim 1, which is directly suitable for actuating a valve and with which it is possible to adjust the valve sensitively, in particular from a remote location, with the aid of the speed change of the electric motor out.

Lösungsolution

Gelöst wird diese Aufgabe durch die im kennzeichnenden Teil des Anspruchs 1 angegebenen Maßnahmen.This object is achieved by the measures specified in the characterizing part of claim 1.

Zeichnungdrawing

Zwei Ausführungsbeispiele der Erfindung sind in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert. Es zeigen Figur 1 einen elektroyhdraulischen Stellantrieb in schematischer Darstellung, Figur 2 ein zweites, abgewandeltes Ausführungsbeispiel.Two embodiments of the invention are shown in the drawing and explained in more detail in the following description. 1 shows an electrohydraulic actuator in a schematic representation, FIG. 2 shows a second, modified exemplary embodiment.

Beschreibung der AusführungsbeispieleDescription of the embodiments

In Figur 1 ist mit 10 ein Gleichstrommotor bezeichnet, der eine reversierbare hydrostatische pumpe 11, insbesondere eine Zahnradpumpe, antreibt. An diese sind zwei Förderleitungen 12 bzw. 13 angeschlossen, die zu zwei Druckräumen 14, 15 eines Wegeventils 16 führen. In diesem ist ein Steuerschieber 17 geführt, der beidseitig von Federn 18 bzw. 19 belastet und zentriert ist. An den Druckraum 14 ist eine Leitung 20 angeschlossen, die zu einem Behälter 21 führt und in der eine verstellbare Drossel 22 angeordnet ist.In FIG. 1, 10 denotes a direct current motor which drives a reversible hydrostatic pump 11, in particular a gear pump. Two delivery lines 12 and 13, which lead to two pressure chambers 14, 15 of a directional control valve 16, are connected to these. In this a control slide 17 is guided, which is loaded on both sides by springs 18 and 19 and centered. A line 20 is connected to the pressure chamber 14, which leads to a container 21 and in which an adjustable throttle 22 is arranged.

An den Druckraum 15 ist ebenfalls eine Leitung 24 angeschlossen, die ebenfalls zum Behälter führt und in der auch eine verstellbare Drossel 25 angeordnet ist. Die Verstellglieder 27 bzw. 28 der beiden Drosseln 22, 25 sind durch ein Koppelglied 29 verbunden und um einen Punkt 30 derart schwenkbar, daß sie gegensinnig verstellt werden.A line 24 is also connected to the pressure chamber 15, which also leads to the container and in which an adjustable throttle 25 is also arranged. The adjusting members 27 and 28 of the two throttles 22, 25 are connected by a coupling member 29 and can be pivoted about a point 30 such that they are adjusted in opposite directions.

Am Steuerschieber 17 ist eine mittige Ringnut 32 ausgebildet, durch welche ein Verbraucheranschluß A bzw. B mit einer zum Behälter 21 führenden Leitung 33 verbunden werden können.A central annular groove 32 is formed on the control slide 17, through which a consumer connection A or B can be connected to a line 33 leading to the container 21.

An die Leitungen 12, 13 sind Leitungen 35, 36 angeschlossen, die zum Behälter 21 führen und in denen jeweils ein Rückschlagventil 37, 38 angeschlossen ist, die sich in Richtung vom Behälter zu den Leitungen 12 bzw. 13 hin zu öffnen vermögen.Lines 35, 36 are connected to lines 12, 13, which lead to container 21 and in each of which a check valve 37, 38 is connected, which can open in the direction from the container to lines 12 and 13, respectively.

Es sei angenommen, daß die Pumpe 11 nach Anlaufen des Elektromotors 10 Druckmittel über die Leitung 36 ansaugt und in die Leitung 12 verdrängt. In dieser sowie im Druckraum) 4 baut sich nun ein Druck auf, der abhängig ist vom Durchflußwiderstand der Drossel 22 und der Kraft der Feder 19. Der Steuerschieber 17 bewegt sich nun entgegen der Kraft der Feder 19. Aus dem Druckraum 15 kann Druckmittel über die Leitung 24 und die Drossel 25 zum Behälter 21 und über die Leitung 13 zur Pumpe 11 abfließen.It is assumed that the pump 11 sucks in pressure medium via line 36 after displacement of the electric motor 10 and displaces it into line 12. In this and in the pressure chamber) 4, a pressure builds up, which is dependent on the flow resistance of the throttle 22 and the force of the spring 19. The control slide 17 now moves against the force of the spring 19. Pressure medium 15 can flow from the pressure chamber Drain line 24 and throttle 25 to tank 21 and via line 13 to pump 11.

Fördert die Pumpe 11 Druckmittel in die Leitung 13, so baut sich im Druckraum 15 Druck auf, und der Steuerschieber 17 wird entgegen der Kraft der Feder 18 nach links verschoben. Dies geschieht genauso wie zuvor beschrieben. Da sich die Drosseln gegensinnig in gleichem Maße öffnen und schließen, sind die Abströmquerschnitte aus den Druckräumen 14 und 15 stets gleich. Durch das Koppelglied 29 können die Durchflußquerschnitte der Drosseln 22, 25 verändert werden und damit die Verstellgeschwindigkeit des Steuerschiebers 17 beeinflußt werden, d. h. nicht nur durch Andern der Drehzahl des Elektromotors 10.If the pump 11 pumps pressure medium into the line 13, pressure builds up in the pressure chamber 15 and the control slide 17 is displaced to the left against the force of the spring 18. This is done exactly as previously described. Since the throttles open and close to the same extent in opposite directions, the outflow cross sections from the pressure chambers 14 and 15 are always the same. Through the coupling member 29, the flow cross sections of the throttles 22, 25 can be changed and thus the adjustment speed of the control slide 17 can be influenced, i. H. not only by changing the speed of the electric motor 10.

Das Ausführungsbeispiel nach Figur 2 unterscheidet von demjenigen nach Figur 1 lediglich dadurch, daß hier die Leitungen 35, 36 entfallen. Die Pumpe 11 und das Wegeventil 17 arbeiten im geschlossenen Kreislauf. Es können aber die Drosseln 22, 25 zum Ansaugen von Druckmittel aus dem Behälter 21 verwendet werden.The embodiment of Figure 2 differs from that of Figure 1 only in that the lines 35, 36 are omitted. The pump 11 and the directional control valve 17 operate in a closed circuit. However, the throttles 22, 25 can be used to draw pressure medium from the container 21.

Claims (2)

1. Electrohydraulic positioning drive having a reversible pump (11) which is driven by an electric motor (10) and delivers pressure medium, in each case via one of two pressure lines (12, 13), to a double-acting adjusting member (16), an adjustable throttle means (22, 25) being connected onto the pressure lines, by means of which throttle means (22, 25) a connection can be made to a chamber of low pressure, characterised in that the adjusting member is a directional control valve (16), the slide valve (17) of which is acted upon on both sides by centering springs (18, 19), in that a throttle valve (22, 25) is connected on each directional control valve chamber (14,15) acted upon by the pump, which throttle valve (22, 25) is connected to a chamber (21) of lower pressure, and in that the throttle valves are coupled and are adjustable in opposite directions.
2. Drive according to Claim 1, characterised in that the electric motor (10) is a direct current motor.
EP82110794A 1981-12-05 1982-11-23 Electro-hydraulic actuator Expired EP0081703B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3148174 1981-12-05
DE19813148174 DE3148174A1 (en) 1981-12-05 1981-12-05 ELECTROHYDRAULIC ACTUATOR

Publications (2)

Publication Number Publication Date
EP0081703A1 EP0081703A1 (en) 1983-06-22
EP0081703B1 true EP0081703B1 (en) 1986-02-26

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ID=6147968

Family Applications (1)

Application Number Title Priority Date Filing Date
EP82110794A Expired EP0081703B1 (en) 1981-12-05 1982-11-23 Electro-hydraulic actuator

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EP (1) EP0081703B1 (en)
JP (1) JPS58102807A (en)
DE (2) DE3148174A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE202013002862U1 (en) 2013-03-26 2013-04-23 BUKO Solutions GmbH adjustment
DE102013005127A1 (en) 2013-03-26 2014-10-02 BUKO Solutions GmbH adjustment

Families Citing this family (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4569372A (en) * 1984-08-28 1986-02-11 Commercial Shearing, Inc. Remote valve operators
GB8629750D0 (en) * 1986-12-12 1987-01-21 British Aerospace Electro-hydraulic actuator assembly
JPH03501597A (en) * 1988-10-04 1991-04-11 アルフレツド・デヴエス・ゲー・エム・ベーハー Automotive hydraulic power steering system
DE4030107A1 (en) * 1990-09-22 1992-03-26 Steag Ag HYDRAULIC ACTUATOR FOR CONTROL AND CONTROL ARMATURES
DK0665381T3 (en) * 1994-01-28 1999-06-07 Pleiger Maschf Paul Device for operating hydraulically actuated luminaires
DE19600650C2 (en) * 1996-01-10 2003-05-28 Trinova Gmbh Drive for a hydraulic double-acting actuator
DE19958257B4 (en) * 1999-12-03 2008-04-24 Bosch Rexroth Aktiengesellschaft Semi-open hydraulic circuit
JP2004263645A (en) * 2003-03-03 2004-09-24 Opton Co Ltd Hydraulic device
US20060168955A1 (en) * 2005-02-03 2006-08-03 Schlumberger Technology Corporation Apparatus for hydraulically energizing down hole mechanical systems
JP4356623B2 (en) 2005-02-03 2009-11-04 ダイキン工業株式会社 Fluid pressure unit and method for controlling fluid pressure unit
DE102008034301B4 (en) * 2007-12-04 2019-02-14 Robert Bosch Gmbh Hydraulic system with an adjustable quick-release valve
CN103429911B (en) * 2011-03-07 2017-02-08 莫戈公司 Subsea actuation system
DE102013008792B4 (en) * 2013-05-23 2016-12-22 Thomas Magnete Gmbh Method and device for adjusting a hydraulic variable displacement pump
CN105003481B (en) * 2015-07-01 2017-02-01 天津大学 Integrated variable-damping hydraulic support system

Citations (2)

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Publication number Priority date Publication date Assignee Title
US4218884A (en) * 1978-11-08 1980-08-26 Harold Gold Hydraulic speed governor
DE2940403A1 (en) * 1979-10-05 1981-04-09 G.L. Rexroth Gmbh, 8770 Lohr DEVICE FOR REGULATING AN ACTUATOR, IN PARTICULAR REGULATING THE LIFTING DEVICE OF A TRACTOR, COMBINE HARNESS OR THE LIKE.

Family Cites Families (5)

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Publication number Priority date Publication date Assignee Title
CH201066A (en) * 1937-10-26 1938-11-15 Escher Wyss Maschf Ag Hydraulic servo motor for actuating rotating closing elements.
DE841094C (en) * 1950-09-05 1952-06-13 Elektro Mechanik G M B H Electro-hydraulic adjusting drive with slide control
US2916879A (en) * 1956-04-04 1959-12-15 John T Gondek Combination hydraulic power unit
FR1518913A (en) * 1967-02-15 1968-03-29 Puma Soc Control device for a double-acting cylinder or the like
DE1916266A1 (en) * 1968-05-21 1970-10-08 Bbc Brown Boveri & Cie Electrohydraulic actuator

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4218884A (en) * 1978-11-08 1980-08-26 Harold Gold Hydraulic speed governor
DE2940403A1 (en) * 1979-10-05 1981-04-09 G.L. Rexroth Gmbh, 8770 Lohr DEVICE FOR REGULATING AN ACTUATOR, IN PARTICULAR REGULATING THE LIFTING DEVICE OF A TRACTOR, COMBINE HARNESS OR THE LIKE.

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE202013002862U1 (en) 2013-03-26 2013-04-23 BUKO Solutions GmbH adjustment
DE102013005127A1 (en) 2013-03-26 2014-10-02 BUKO Solutions GmbH adjustment

Also Published As

Publication number Publication date
DE3148174A1 (en) 1983-06-09
JPS58102807A (en) 1983-06-18
DE3269488D1 (en) 1986-04-03
EP0081703A1 (en) 1983-06-22

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