EP0016862A1 - Control device for a hydraulic system - Google Patents

Control device for a hydraulic system Download PDF

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Publication number
EP0016862A1
EP0016862A1 EP79104835A EP79104835A EP0016862A1 EP 0016862 A1 EP0016862 A1 EP 0016862A1 EP 79104835 A EP79104835 A EP 79104835A EP 79104835 A EP79104835 A EP 79104835A EP 0016862 A1 EP0016862 A1 EP 0016862A1
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EP
European Patent Office
Prior art keywords
pump
consumer
way valve
pressure medium
generator
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Granted
Application number
EP79104835A
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German (de)
French (fr)
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EP0016862B1 (en
Inventor
Richard Ing. Grad. Friedrich
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Robert Bosch GmbH
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Robert Bosch GmbH
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    • 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
    • F15B21/00—Common features of fluid actuator systems; Fluid-pressure actuator systems or details thereof, not covered by any other group of this subclass
    • F15B21/08—Servomotor systems incorporating electrically operated control means
    • F15B21/087—Control strategy, e.g. with block diagram
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10S—TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S60/00—Power plants
    • Y10S60/911—Fluid motor system incorporating electrical system

Definitions

  • the invention relates to a control device for a hydraulic system according to the preamble of the main claim.
  • a control device for a hydraulic system according to the preamble of the main claim.
  • the direction of the consumer is reversed, e.g. a hydraulic cylinder or a hydraulic motor - by means of a directional valve which is actuated, for example, by hand or by pressure valves or electromagnets.
  • Such actuation devices have the disadvantage that the consumer accelerates and decelerates suddenly, at least when the directional valve is actuated quickly, which is undesirable in many cases.
  • the control device with the characterizing features of the main claim has the advantage that even if the directional valve designed as a multi-way valve is actuated quickly, the consumer is accelerated and decelerated smoothly, especially when switching from one consumer to another, if the pump optionally feeds several drives .
  • Figure 1 shows a control device for a hydraulic system in a schematic representation
  • Figure 2 shows a diagram.
  • An adjustable but not reversible pump 10 sucks pressure medium from a container 11 and conveys it via a delivery line 12 to a 4/3-way valve 13 with the switching positions I, II and III.
  • the directional control valve 13 is actuated electromagnetically by two magnets 14, 15. From the directional control valve 13, two lines 16, 17 lead to a double valve via an electromagnetically actuated 4/2-way valve 18 kenden hydraulic cylinder 19. From line 16 leads a line 20, from line 17 a line 21 to an electromagnetically actuated 4/2-way valve 23, from which the lines lead to a hydraulic motor with changing direction of movement 24.
  • the setting of the stroke-generating member 26 of the pump '10 is carried out with the aid of a servo motor 27.
  • An electric setpoint generator 28, 'e.g. B. uses a potentiometer with a hand lever, the output signal 28 'can be changed arbitrarily - ie also in a step-like manner - between plus maximum and minus maximum.
  • This rapidly changing signal 28 ' is sent to a ramp generator 29' which e.g. can be a capacitor or a choke, which forms a signal 29 'with a defined positive or negative slope.
  • a magnitude generator 30 which can be a full-wave rectifier, for example, the signal 29 'is rectified so that the servo motor 27 always receives a signal 30' which changes between zero and a maximum according to the ability of the pump, but does not change its direction .
  • the output signal 29 'of the ramp generator 29 is additionally fed to a switching amplifier 31 and 32; these can be Schmidt triggers, for example.
  • the switching amplifier 31 responds with a small threshold value 33 - see FIG. 2 - to positive signal 29 ', the switching amplifier 32, however, also with a small threshold value 34 to negative signal 29'.
  • This is a directional decision available for the pressure medium flow.
  • the output signals 31 'and 32' of the switching amplifiers 31, 32 excite the magnets 14, 15, the direction of the pressure medium flow is predetermined by the directional control valve 13.
  • the respective gap 35 between the signals 31 ', 32' is used to carry out further switching operations, e.g. B.
  • the pump 10 using the directional control valves 13, 18 and 23 to switch to the hydraulic motor 24, which happens at zero flow rate and thus bumpless. If the directional control valve 18 is in its blocking position II, the pressure medium is supplied to the hydraulic motor 24 via the lines 20, 21 and the directional control valve 23 which is then in the flow position I.
  • a non-reversible pump with a variable delivery rate acquires the character of a reversible pump.
  • the defined increase or decrease in the pressure medium flow results in a defined acceleration or deceleration of the consumers, and shocks are avoided.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Fluid-Pressure Circuits (AREA)

Abstract

Die Erfindung bezieht sich auf eine Steuereinrichtung für eine Hydraulikanlage mit einer verstellbaren, aber nicht umkehrbaren Pumpe (10), die Druckmittel zu wenigstens einem Verbraucher (19, 24) steuert. Wesentlich ist, daß durch definierte Zu- bzw. Abnahme des Druckmitteistroms eine definierte Beschleunigung bzw. Verzögerung der Verbraucher erreicht wird, wobei die Einrichtung durch verschiedene elektronische Steuerglieder so ausgelegt ist, daß Beschleunigungsstöße vermieden werden. Die Pumpe (26) ist verstellbar aber nicht reversierbar; durch die Art der Steuerung erhält sie jedoch den Charakter einer reversierbaren Pumpe.

Figure imgaf001
The invention relates to a control device for a hydraulic system with an adjustable but not reversible pump (10) that controls pressure medium to at least one consumer (19, 24). It is essential that a defined acceleration or deceleration of the consumers is achieved by a defined increase or decrease in the pressure medium flow, the device being designed by various electronic control elements in such a way that acceleration surges are avoided. The pump (26) is adjustable but not reversible; the type of control gives it the character of a reversible pump.
Figure imgaf001

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einer Steuereinrichtung für eine Hydraulikanlage nach der Gattung des Hauptanspruchs. Bei derartigen bekannten Steuereinrichtungen erfolgt die Richtungsumkehr des Verbrauchers, z.B. ein Hydrozylinder oder ein Hydromotor - durch ein Richtungsventil, das beispielsweise von Hand oder durch Druckventile oder Elektromagnete betätigt wird. Solche Betätigungseinrichtungen haben den Nachteil, daß der Verbraucher mindestens bei schnellem Betätigen des Richtungsventils ruckartig beschleunigt und verzögert, was in vielen Fällen unerwünscht ist.The invention relates to a control device for a hydraulic system according to the preamble of the main claim. In such known control devices, the direction of the consumer is reversed, e.g. a hydraulic cylinder or a hydraulic motor - by means of a directional valve which is actuated, for example, by hand or by pressure valves or electromagnets. Such actuation devices have the disadvantage that the consumer accelerates and decelerates suddenly, at least when the directional valve is actuated quickly, which is undesirable in many cases.

Vorteile der ErfindungAdvantages of the invention

Die erfindungsgemäße Steuereinrichtung mit den kennzeichnenden Merkmalen des Hauptanspruchs hat demgegenüber den Vorteil, daß auch bei schnellem Betätigen des als Mehrwegeventil ausgebildeten Richtungsventils der Verbraucher weich beschleunigt und verzögert wird, insbesondere auch beim Umschalten von einem Verbraucher auf einen anderen, falls die Pumpe wahlweise mehrere Antriebe speist.The control device according to the invention with the characterizing features of the main claim has the advantage that even if the directional valve designed as a multi-way valve is actuated quickly, the consumer is accelerated and decelerated smoothly, especially when switching from one consumer to another, if the pump optionally feeds several drives .

Durch die in den Unteransprüchen aufgeführten Maßnahmen sind vorteilhafte Weiterbildungen und Verbesserungen der im Hauptanspruch angegebenen Steuereinrichtung möglich.Advantageous further developments and improvements of the control device specified in the main claim are possible through the measures listed in the subclaims.

Zeichnungdrawing

Ein Ausführungsbeispiel der Erfindung ist in der Zeichnung dargestellt und in der nachfolgenden Beschreibung näher erläutert. Es zeigen Figur 1 eine Steuereinrichtung für eine Hydraulikanlage in schematischer Darstellung, Figur 2 ein Diagramm.An embodiment of the invention is shown in the drawing and explained in more detail in the following description. Figure 1 shows a control device for a hydraulic system in a schematic representation, Figure 2 shows a diagram.

Beschreibung des AusführungsbeispielsDescription of the embodiment

Eine verstellbare, aber nicht umkehrbare Pumpe 10 saugt Druckmittel aus einem Behälter 11 und fördert es über eine Förderleitung 12 zu einem 4/3-Wegeventil 13 mit den Schaltstellungen I, II und III. Das Wegeventil 13 wird elektromagnetisch betätigt durch zwei Magnete 14, 15. Vom Wegeventil 13 führen zwei Leitungen 16, 17 über ein elektromagnetisch betätigbares 4/2-Wegeventil 18 zu einem doppeltwirkenden Hydrozylinder 19. Von der Leitung 16 führt eine Leitung 20, von der Leitung 17 eine Leitung 21 zu einem elektromagnetisch betätigbare 4/2-Wegeventil 23, von dem die Leitungen zu einem Hydromotor mit wechselnder Bewegungsrichtung 24 führen.An adjustable but not reversible pump 10 sucks pressure medium from a container 11 and conveys it via a delivery line 12 to a 4/3-way valve 13 with the switching positions I, II and III. The directional control valve 13 is actuated electromagnetically by two magnets 14, 15. From the directional control valve 13, two lines 16, 17 lead to a double valve via an electromagnetically actuated 4/2-way valve 18 kenden hydraulic cylinder 19. From line 16 leads a line 20, from line 17 a line 21 to an electromagnetically actuated 4/2-way valve 23, from which the lines lead to a hydraulic motor with changing direction of movement 24.

Die Einstellung des huberzeugenden Glieds 26 der Pumpe '10 erfolgt mit Hilfe eines Servomotors 27. Für die Vorgabe des Druckmittelstroms ist ein elektrischer Sollwertgeber 28, 'z. B. ein Potentiometer mit Handhebel verwendet, dessen Ausgangssignal 28' willkürlich - also auch sprungförmig - zwischen Plus Maximum und Minus Maximum veränderbar ist. Dieses sich schnell ändernde Signal 28' wird einem Rampenbildner 29', der z.B. ein Kondensator oder eine Drossel sein kann, zugeführt, der daraus ein Signal 29' mit definierter positiver oder negativer Steigung formt. Diese Ströme sind im Diagramm nach der Figur 2 über der Zeit t graphisch dargestellt. In einem Betragsbildner 30, der beispielsweise ein Vollwellengleichrichter sein kann, wird das Signal 29' gleichgerichtet, so daß der Servomotor 27 stets ein Signal 30' erhält, das entsprechend der Fähigkeit der Pumpe sich zwischen Null und einem Maximum ändert, aber nicht seine Richtung wechselt.The setting of the stroke-generating member 26 of the pump '10 is carried out with the aid of a servo motor 27. An electric setpoint generator 28, 'e.g. B. uses a potentiometer with a hand lever, the output signal 28 'can be changed arbitrarily - ie also in a step-like manner - between plus maximum and minus maximum. This rapidly changing signal 28 'is sent to a ramp generator 29' which e.g. can be a capacitor or a choke, which forms a signal 29 'with a defined positive or negative slope. These currents are shown graphically over time t in the diagram according to FIG. In a magnitude generator 30, which can be a full-wave rectifier, for example, the signal 29 'is rectified so that the servo motor 27 always receives a signal 30' which changes between zero and a maximum according to the ability of the pump, but does not change its direction .

Das Ausgangssignal 29' des Rampenbildners 29 wird zusätzlich je einem Schaltverstärker 31 und 32 zugeführt; dies können beispielsweise Schmidt-Trigger sein. Der Schaltverstärker 31 spricht mit einem kleinen Schwellwert 33 - siehe Figur 2 - auf positive Signal 29' an, der Schaltverstärker 32 dagegen ebenfalls mit einem kleinen Schwellwert 34 auf negative Signal 29'. Damit ist ein Richtungsentscheid für den Druckmittelstrom vorhanden. In dem die Ausgangssignale 31' und 32' der Schaltverstärker 31, 32 die Magnete 14, 15 erregen, wird die Richtung des Druckmittelstroms durch das Wegeventil 13 vorgegeben. Die jeweilige Lücke 35 zwischen den Signalen 31', 32' wird dazu verwendet, weitere Schaltvorgänge zu vollziehen, z. B. die Pumpe 10 mit Hilfe der Wegeventile 13, 18 und 23 auf den Hydromotor 24 umzuschalten, was bei Förderstrom Null und damit stoßfrei geschieht. Befindet sich das Wegeventil 18 in seiner Sperrstellung II, so wird das Druckmittel über die Leitungen 20, 21 und das sich dann in Durchflußstellung I befindliche Wegeventil 23 dem Hydromotor 24 zugeführt.The output signal 29 'of the ramp generator 29 is additionally fed to a switching amplifier 31 and 32; these can be Schmidt triggers, for example. The switching amplifier 31 responds with a small threshold value 33 - see FIG. 2 - to positive signal 29 ', the switching amplifier 32, however, also with a small threshold value 34 to negative signal 29'. This is a directional decision available for the pressure medium flow. In which the output signals 31 'and 32' of the switching amplifiers 31, 32 excite the magnets 14, 15, the direction of the pressure medium flow is predetermined by the directional control valve 13. The respective gap 35 between the signals 31 ', 32' is used to carry out further switching operations, e.g. B. the pump 10 using the directional control valves 13, 18 and 23 to switch to the hydraulic motor 24, which happens at zero flow rate and thus bumpless. If the directional control valve 18 is in its blocking position II, the pressure medium is supplied to the hydraulic motor 24 via the lines 20, 21 and the directional control valve 23 which is then in the flow position I.

Man erreicht mit obiger Einrichtung, daß eine nicht reversierbare Pumpe mit veränderlicher Fördermenge den Charakter einer reversierbaren Pumpe erhält. Durch die definierte Zu- bzw. Abnahme des Druckmittelstroms erhält man eine definierte Beschleunigung bzw. Verzögerung der Verbraucher, Stöße werden vermieden. Diese Vorteile sind auch bei Umschalten der Pumpe auf einen andereh Verbraucher gegeben, wobei die Umschaltung stoßfrei erfolgt.It is achieved with the above device that a non-reversible pump with a variable delivery rate acquires the character of a reversible pump. The defined increase or decrease in the pressure medium flow results in a defined acceleration or deceleration of the consumers, and shocks are avoided. These advantages also exist when the pump is switched to another consumer, the switchover taking place smoothly.

Claims (3)

1. Steuereinrichtung für eine Hydraulikanlage mit einer verstellbaren, nicht umkehrbaren Pumpe, die Druckmittel zu mindestens einem Verbraucher steuert, dem zwecks wechselnder Bewegungsrichtung ein Mehrwegeventil zugeordnet ist, das über einen elektrischen Sollwertgeber (28) gesteuert ist, dadurch gekennzeichnet, daß das Ausgangssignal (28') des Sollwertgebers (28) willkürlich zwischen einem Plus- und Minus-Maximum veränderbar ist und einem elektronischen Rampenbildner (29) zugeführt wird, der daraus ein Ausgangssignal (29') mit definierter positiver bzw. negativer Steigung formt, das in einem elektrischen Betragsbildner (30) gleichgerichtet wird und einem Servomotor (27) zwecks Einstellung der Pumpe (10) zugeleitet wird, und daß das Ausgangssignal (29') des Rampenbildners (21) auch mindestens einem elektrischen Schaltverstärker (31, 32) zugeführt wird, welcher ein Signal (31', 32') für die Einstellung des Mehrwegeventils (13) liefert.1. Control device for a hydraulic system with an adjustable, non-reversible pump that controls pressure medium to at least one consumer, which is assigned a multi-way valve for the purpose of changing direction of movement, which is controlled via an electrical setpoint generator (28), characterized in that the output signal (28 ') of the setpoint generator (28) can be changed arbitrarily between a plus and minus maximum and is supplied to an electronic ramp generator (29), which forms an output signal (29') therefrom with a defined positive or negative slope, which is generated in an electrical amount generator (30) is rectified and fed to a servo motor (27) for the purpose of adjusting the pump (10), and that the output signal (29 ') of the ramp generator (21) is also supplied to at least one electrical switching amplifier (31, 32), which receives a signal (31 ', 32') for the setting of the multi-way valve (13) provides. 2. Einrichtung nach Anspruch 1, dadurch gekennzeichnet, daß das Mehrwegeventil (13) als Elektromagnetventil mit zwei Schaltmagneten (14, 15) ausgebildet ist, die von den Signalen (31', 32') der Schaltverstärker (31, 32) gesteuert sind.2. Device according to claim 1, characterized in that the multi-way valve (13) is designed as an electromagnetic valve with two switching magnets (14, 15) which are controlled by the signals (31 ', 32') of the switching amplifier (31, 32). 3. Einrichtung nach Anspruch 1 und/oder 2, dadurch gekennzeichnet, daß die zwischen den Signalen (31', 32') gebildete zeitliche Lücke (33 bis 35) zu weiteren Schaltvorgängen benutzt wird, insbesondere zu einer Druckmittelsteuerung der Pumpe zu wenigstens einem weiteren Verbraucher (24), wobei dem Mehrwegeventil (13) ein jedem Verbraucher zugeordnetes Steuerventil (18, 23) parallel geschaltet ist.3. Device according to claim 1 and / or 2, characterized in that the time gap formed between the signals (31 ', 32') (33 to 35) is used for further switching operations, in particular for a pressure medium control of the pump to at least one other Consumer (24), a control valve (18, 23) assigned to each consumer being connected in parallel to the multi-way valve (13).
EP79104835A 1979-01-22 1979-12-03 Control device for a hydraulic system Expired EP0016862B1 (en)

Applications Claiming Priority (2)

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DE2902264 1979-01-22
DE19792902264 DE2902264A1 (en) 1979-01-22 1979-01-22 CONTROL DEVICE FOR A HYDRAULIC SYSTEM

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EP0016862A1 true EP0016862A1 (en) 1980-10-15
EP0016862B1 EP0016862B1 (en) 1982-02-03

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0061759A1 (en) * 1981-03-30 1982-10-06 Hitachi Construction Machinery Co., Ltd. Control system for hydraulic circuit means including a variable displacement pump and actuator means
FR2633987A1 (en) * 1988-07-08 1990-01-12 Kubota Ltd HYDRAULIC CIRCUIT FOR WORK VEHICLE
CN107131159A (en) * 2017-06-20 2017-09-05 北京交通大学 Electrohydrostatic actuator under gravitational load

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DE3222008A1 (en) * 1982-06-11 1983-12-15 Sperry-Vickers Zweigniederlassung der Sperry GmbH, 6380 Bad Homburg HYDROSTATIC OR PNEUMATIC DRIVE AND METHOD FOR ITS OPERATION
US4655039A (en) * 1985-06-20 1987-04-07 The Raymond Corporation Lift system
US4741159A (en) * 1986-04-08 1988-05-03 Vickers, Incorporated Power transmission
DE3716200C2 (en) * 1987-05-14 1997-08-28 Linde Ag Control and regulating device for a hydrostatic drive unit and method for operating one
DE4303760C2 (en) * 1993-02-09 1995-12-14 Procontrol Ag Method and device for hydraulic mass drive, in particular of injection molding machines
DE4327313C2 (en) * 1993-08-13 2001-07-05 Mannesmann Rexroth Ag Process for regulating the pressure of a hydrostatic machine with an adjustable delivery volume
DE19743801A1 (en) * 1997-10-02 1999-04-08 Claas Selbstfahr Erntemasch Device for controlling a hydraulic cylinder in a self-propelled harvesting machine
DE102009020046B4 (en) * 2009-05-05 2012-08-16 Kraussmaffei Technologies Gmbh Electrically operated hydraulic drive device as auxiliary unit for an injection molding machine
RU2534128C1 (en) * 2013-03-28 2014-11-27 Федеральное государственное бюджетное образовательное учреждение высшего профессионального образования "Курганский государственный университет" Motion control system for high-speed transport machine
DE102014226617A1 (en) * 2014-12-19 2016-06-23 Robert Bosch Gmbh Drive control device for an electro-hydraulic drive

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US3712180A (en) * 1970-11-27 1973-01-23 Gen Electric Bilateral servo controlled manipulator
DE2808694A1 (en) * 1978-03-01 1979-09-06 Bosch Gmbh Robert Positioning device for hydraulic drive - has hydraulic motor fed by servo device controlled by voltage signal from electronic circuit

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US2643515A (en) * 1950-10-17 1953-06-30 Chester A Harsch Electric control system for expansible motor operated boom
DE1807172A1 (en) * 1968-11-06 1970-06-11 Bosch Gmbh Robert Device for the electro-hydraulic remote control of hydraulic directional control valves
US3946284A (en) * 1974-08-19 1976-03-23 Rexnord, Inc. Circuit for controlling damp shock loading
US3952509A (en) * 1975-04-10 1976-04-27 Allis-Chalmers Corporation Hydraulic system combining open center and closed center hydraulic circuits
US3956772A (en) * 1975-07-11 1976-05-18 The United States Of America As Represented By The Secretary Of The Army Control system for pre-inflation of pilot's G-suit
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Patent Citations (2)

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US3712180A (en) * 1970-11-27 1973-01-23 Gen Electric Bilateral servo controlled manipulator
DE2808694A1 (en) * 1978-03-01 1979-09-06 Bosch Gmbh Robert Positioning device for hydraulic drive - has hydraulic motor fed by servo device controlled by voltage signal from electronic circuit

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0061759A1 (en) * 1981-03-30 1982-10-06 Hitachi Construction Machinery Co., Ltd. Control system for hydraulic circuit means including a variable displacement pump and actuator means
FR2633987A1 (en) * 1988-07-08 1990-01-12 Kubota Ltd HYDRAULIC CIRCUIT FOR WORK VEHICLE
CN107131159A (en) * 2017-06-20 2017-09-05 北京交通大学 Electrohydrostatic actuator under gravitational load

Also Published As

Publication number Publication date
EP0016862B1 (en) 1982-02-03
US4375747A (en) 1983-03-08
DE2962071D1 (en) 1982-03-11
DE2902264A1 (en) 1980-07-24

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