EP0089578B1 - Hydraulic system - Google Patents

Hydraulic system Download PDF

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Publication number
EP0089578B1
EP0089578B1 EP83102414A EP83102414A EP0089578B1 EP 0089578 B1 EP0089578 B1 EP 0089578B1 EP 83102414 A EP83102414 A EP 83102414A EP 83102414 A EP83102414 A EP 83102414A EP 0089578 B1 EP0089578 B1 EP 0089578B1
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EP
European Patent Office
Prior art keywords
line
control valve
flap
directional control
unit according
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
EP83102414A
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German (de)
French (fr)
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EP0089578A2 (en
EP0089578A3 (en
Inventor
Horst Dr. Dipl.-Ing. Hesse
Hartmut Dipl.-Ing. Sandau
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
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Filing date
Publication date
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Publication of EP0089578A2 publication Critical patent/EP0089578A2/en
Publication of EP0089578A3 publication Critical patent/EP0089578A3/en
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Publication of EP0089578B1 publication Critical patent/EP0089578B1/en
Expired legal-status Critical Current

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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
    • F15B11/00—Servomotor systems without provision for follow-up action; Circuits therefor
    • F15B11/08—Servomotor systems without provision for follow-up action; Circuits therefor with only one servomotor

Definitions

  • the invention is based on a hydraulic system according to the preamble of the main claim.
  • a hydraulic system according to the preamble of the main claim.
  • the entire pressure medium conveyed by the pump must be drained off via a pressure relief valve in the “lowering” operating state. This means not only a loss of energy, but also the oil is heated in an undesirable manner by the flow resistance at the pressure relief valve.
  • the hydraulic system according to the invention with the characterizing features of the main claim has the advantage that, when a single-acting working cylinder is connected to the hydraulic network, a direct, resistance-free discharge of the pump to the container is possible in the "lowering" operating state. This means significant energy savings.
  • a pump 10 sucks pressure medium from a container 11 and displaces it into a line 12, which leads to a 4/3-way valve 13. This can take the switch positions I to 111.
  • a pressure relief valve 14 is connected to the delivery line 12 and has a connection to the container 11.
  • a first line 16 leads to a line coupling 17 and a second line 18 to a second line coupling 19.
  • a 2/2-way valve 20 is connected to the line 18, via which a line 21 leads from the line 18 to the container 11 leads.
  • the return line 22 from the directional control valve 13 is also connected to the line 21.
  • a line 24 is connected to the first line coupling 17 and leads to the pressure chamber 25 of a single-acting working cylinder 26.
  • the line coupling 19 can be closed by a flap 27 which is pivotally arranged on a bracket 28 fixed to the housing. At the other end of the lever-like flap 27, a spring 30 engages, which presses the flap 27 onto the line coupling.
  • the directional control valve 20 is operatively connected to the flap 27 and can be shifted by the flap 27 into one of its two switching positions I or 11, 1 being a blocking position.
  • a line 31 shown in dashed lines leads from the line coupling 19 to the other pressure chamber of the working cylinder, which, however, is not further designated.
  • FIG. 2 and 3 shows a practical embodiment.
  • the flap 27 is fastened on an axis 37 and is pressed onto the line coupling 17 by means of two torsion springs 35, 36.
  • a housing is attached to the housing 38 receiving the flap 27 and has a blind bore 40 in which a control slide 41 is guided in a tightly sliding manner. This is pressed with its port set 42 by the force of a spring 43 arranged in the blind bore 40 against the flap 27.
  • the Control slide 41 has an elongated annular groove 44, in the area of which two transverse bores 45, 46 open into the blind bore 40 when the flap 27 is closed.
  • the pressure medium flowing in the line 18 can then - as described above - flow to the container via the transverse bore 45, the annular groove 44, the transverse bore 46 and the line 21. If the flap 27 is folded up for the purpose of connecting a line to the coupling 17, the control slide 41 interrupts the connection between the two transverse bores 45, 46.
  • FIG. 4 shows a modification of that according to FIGS. 2 and 3.
  • a plunger 50 lies against the flap 27.
  • the plunger has a conical region 51 and a part in the part lying in the blind bore 40 on this following cylindrical region 52, against which, when the flap 27 is closed, the tappet 53 of a seat valve 54 bears.
  • the seat valve is open in this operating state. After the flap has been opened for the purpose of connecting a line to the coupling 17, the tappet 53 reaches the end of the conical region 51, as a result of which the seat valve 54 is closed. In this state, no pressure medium can flow from line 18 to line 21, as described at the beginning.

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

Description

Stand der TechnikState of the art

Die Erfindung geht aus von einer Hydraulikanlage nach der Gattung des Hauptanspruchs. Bei einer derartigen bekannten Anlage muß dann, wenn nur ein einfach wirkender Zylinder über die Leitungskupplung an das Leitungsnetz angeschlossen ist, im Betriebszustand "Senken" das gesamte von der Pumpe geförderte Druckmittel über ein Druckbegrenzungsventil abgelassen werden. Dies bedeutet nicht nur einen Energieverlust, sondern durch den Durchflußwiderstand am Druckbegrenzungsventil wird auch das Öl in unerwünschter Weise erwärmt.The invention is based on a hydraulic system according to the preamble of the main claim. In such a known system, if only a single-acting cylinder is connected to the line network via the line coupling, the entire pressure medium conveyed by the pump must be drained off via a pressure relief valve in the “lowering” operating state. This means not only a loss of energy, but also the oil is heated in an undesirable manner by the flow resistance at the pressure relief valve.

Vorteile der ErfindungAdvantages of the invention

Die erfindungsgemäße Hydraulikanlage mit den kennzeichnenden Merkmalen des Hauptanspruchs hat demgegenüber den Vorteil, daß dann, wenn an das Hydrauliknetz ein einfach wirkender Arbeitszylinder angeschlossen ist, im Betriebszustand "Senken" eine direkte, widerstandsfreie Entlastung der pumpe zum Behälter möglich ist. Dies bedeutet eine merkliche Energieeinsparung.The hydraulic system according to the invention with the characterizing features of the main claim has the advantage that, when a single-acting working cylinder is connected to the hydraulic network, a direct, resistance-free discharge of the pump to the container is possible in the "lowering" operating state. This means significant energy savings.

Durch die in den Unteransprüchen aufgeführten Maßnahmen sind vorteilhafte Weiterbildungen und Verbesserungen der im Hauptanspruch angegebenen Merkmale möglich.Advantageous further developments and improvements of the features 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 Hydraulikanlage in schematischer Darstellung,
  • Figur 2 eine Ansicht eines in der Anlage verwendeten Geräts,
  • Figur 3 einen Schnitt längs III-III nach Figur 2,
  • Figur 4 eine weitere Variante eines in der Anlage verwendeten Geräts im Längsschnitt.
An embodiment of the invention is shown in the drawing and explained in more detail in the following description. Show it
  • FIG. 1 shows a hydraulic system in a schematic representation,
  • FIG. 2 shows a view of a device used in the system,
  • FIG. 3 shows a section along III-III according to FIG. 2,
  • Figure 4 shows a further variant of a device used in the system in longitudinal section.

Beschreibung des AusführungsbeispielsDescription of the embodiment

Eine Pumpe 10 saugt aus einem Behälter 11 Druckmittel an und verdrängt es in eine Leitung 12, die zu einem 4/3-Wegeventil 13 führt. Dieses vermag die Schaltstellungen I bis 111 einzunehmen. An die Förderleitung 12 ist ein Druckbegrenzungsventil 14 angeschlossen, das Verbindung zum Behälter 11 hat.A pump 10 sucks pressure medium from a container 11 and displaces it into a line 12, which leads to a 4/3-way valve 13. This can take the switch positions I to 111. A pressure relief valve 14 is connected to the delivery line 12 and has a connection to the container 11.

Vom Ausgang des Wegeventils 13 führt eine erste Leitung 16 zu einer Leitungskupplung 17 und eine zweite Leitung 18 zu einer zweiten Leitungskupplung 19. An die Leitung 18 ist ein 2/2-Wegeventil 20 angeschlossen, über das eine Leitung 21 von der Leitung 18 zum Behälter 11 führt. An die Leitung 21 ist auch die RücklaufLeitung 22 vom Wegeventil 13 angeschlossen.From the outlet of the directional valve 13, a first line 16 leads to a line coupling 17 and a second line 18 to a second line coupling 19. A 2/2-way valve 20 is connected to the line 18, via which a line 21 leads from the line 18 to the container 11 leads. The return line 22 from the directional control valve 13 is also connected to the line 21.

An die erste Leitungskupplung 17 ist eine Leitung 24 angeschlossen, die zum Druckraum 25 eines einfach wirkenden Arbeitszylinders 26 führt.A line 24 is connected to the first line coupling 17 and leads to the pressure chamber 25 of a single-acting working cylinder 26.

Die Leitungskupplung 19 kann durch eine Klappe 27 verschlossen werden, welche an einer gehäusefesten Konsole 28 schwenkbar angeordnet ist. Am anderen Ende der hebelartigen Klappe 27 greift eine Feder 30 an, welche die Klappe 27 auf die Leitungskupplung drückt. Das Wegeventil 20 steht mit der Klappe 27 in Wirkverbindung und kann von dieser in eine seiner beiden Schaltstellungen I oder 11 verschoben werden, wobei 1 eine Sperrstellung ist.The line coupling 19 can be closed by a flap 27 which is pivotally arranged on a bracket 28 fixed to the housing. At the other end of the lever-like flap 27, a spring 30 engages, which presses the flap 27 onto the line coupling. The directional control valve 20 is operatively connected to the flap 27 and can be shifted by the flap 27 into one of its two switching positions I or 11, 1 being a blocking position.

Handelt es sich beim Verbraucher um einen doppeltwirkenden Arbeitszylinder, so führt von der Leitungskupplung 19 eine gestrichelt dargestellte Leitung 31 zum anderen Druckraum des Arbeitszylinders, der allerdings nicht weiter bezeichnet ist.If the consumer is a double-acting working cylinder, a line 31 shown in dashed lines leads from the line coupling 19 to the other pressure chamber of the working cylinder, which, however, is not further designated.

Es sei angenommen, daß - wie in Figur 1 dargestellt - an die Leitungskupplung 17 über die Leitung 24 ein einfach wirkender Arbeitszylinder 26 angeschlossen ist. In der Schaltstellung 111 des Wegeventils 13 gelangt Druckmittel über die Leitung 12, das Wegeventil 13, die Leitung 16, die Leitungskupplung 17 und die Leitung 24 zum Druckraum 25 des Arbeitszylinders 26. Dessen Kolben samt Kolbenstange werden ausgefahren. Da an die Leitungskupplung 19 keine Leitung angeschlossen ist, wird die Leitungskupplung durch die Klappe 27 geschlossen. Ist ein doppeltwirkender Zylinder vorgesehen, so wird die Klappe 27 hochgeklappt, und an die Leitungskupplung 19 wird die Leitung 31 angeschlossen. Durch das Aufklappen der Klappe 27 wird das Wegeventil 20 in seine Sperrstellung I gebracht, so daß keine Verbindung von der Leitung 18 zur Leitung 21 mehr besteht.It is assumed that - as shown in FIG. 1 - a single-acting working cylinder 26 is connected to the line coupling 17 via the line 24. In the switching position 111 of the directional control valve 13, pressure medium passes via the line 12, the directional control valve 13, the line 16, the line coupling 17 and the line 24 to the pressure chamber 25 of the working cylinder 26. Its piston and piston rod are extended. Since no line is connected to the line coupling 19, the line coupling is closed by the flap 27. If a double-acting cylinder is provided, the flap 27 is folded up and the line 31 is connected to the line coupling 19. By opening the flap 27, the directional valve 20 is brought into its blocking position I, so that there is no longer a connection from line 18 to line 21.

Soll der Kolben des an die Leitungskupplung 17 angeschlossenen einfach wirkenden Arbeitszylinders 26 gesenkt werden, so wird das Wegeventil 13 in seine Schaltstellung gebracht. Die Klappe 27 ist geschlossen, das Wegeventil 20 befindet sich in seiner Schaltstellung 11. Nun kann Druckmittel aus dem Druckraum 25 des Arbeitszylinders über die Leitungen 24,16 sowie das Wegeventil 13 und die Leitung 22 in den Behälter abfließen. Das von der Pumpe weiterhin geförderte Druckmittel fließt nun über die Leitung 12 und das Wegeventil 13 in die Leitung 18 und von dort über das Wegeventil 20 und die Leitung 21 ohne merklichen Widerstand zum Behälter. Bei bekannten Anlagen mußte dieses Druckmittel über das Druckbegrenzungsventil 14 abgelassen werden, was einen wesentlichen Energieverlust bedeutete.If the piston of the single-acting working cylinder 26 connected to the line coupling 17 is to be lowered, the directional control valve 13 is brought into its switching position. The flap 27 is closed, the directional control valve 20 is in its switch position 11. Now pressure medium can flow out of the pressure chamber 25 of the working cylinder via the lines 24, 16 as well as the directional control valve 13 and the line 22 into the container. The pressure medium pumped further by the pump now flows via line 12 and directional valve 13 into line 18 and from there via directional valve 20 and line 21 to the container without noticeable resistance. In known systems, this pressure medium had to be released via the pressure relief valve 14, which meant a substantial loss of energy.

Wenn ein doppeltwirkender Arbeitszylinder angeordnet ist, ergibt sich diese Schwierigkeit nicht, und das Wegeventil 20 befindet sich bei geöffneter Klappe 27 in seiner Sperrstellung I; die Durchflußstellung 11 wird nun nicht benötigt.If a double-acting working cylinder is arranged, this difficulty does not arise, and the directional control valve 20 is in its blocking position I when the flap 27 is open; the flow position 11 is now not required.

Das Ausführungsbeispiel nach Figur 2 und 3 zeigt eine praktische Ausführungsform. Die Klappe 27 ist auf einer Achse 37 befestigt und wird mittels zweier Drehfedern 35, 36 auf die Leitungskupplung 17 gedrückt. An das die Klappe 27 aufnehmende Gehause 38 ist ein Gehäuse angebaut, das eine Sackbohrung 40 aufweist, in der ein Steuerschieber 41 dicht gleitend geführt ist. Dieser wird mit seinem Portsatz 42 durch die Kraft einer in der Sackbohrung 40 angeordneten Feder 43 an die Klappe 27 gedrückt. Der Steuerschieber 41 hat eine längliche Ringnut 44, in deren Bereich zwei Querbohrungen 45, 46 in die Sackbohrung 40 münden, wenn die Klappe 27 geschlossen ist. Das in der Leitung 18 fließende Druckmittel kann dann - wie oben beschrieben - über die Querbohrung 45, die Ringnut 44, die Querbohrung 46 und die Leitung 21 zum Behälter fließen. Wird die Klappe 27 zwecks Anschluß einer Leitung an die Kupplung 17 hochgeklappt, dann unterbricht der Steuerschieber 41 die Verbindung zwischen den beiden Querbohrung 45, 46.The embodiment of Figures 2 and 3 shows a practical embodiment. The flap 27 is fastened on an axis 37 and is pressed onto the line coupling 17 by means of two torsion springs 35, 36. A housing is attached to the housing 38 receiving the flap 27 and has a blind bore 40 in which a control slide 41 is guided in a tightly sliding manner. This is pressed with its port set 42 by the force of a spring 43 arranged in the blind bore 40 against the flap 27. The Control slide 41 has an elongated annular groove 44, in the area of which two transverse bores 45, 46 open into the blind bore 40 when the flap 27 is closed. The pressure medium flowing in the line 18 can then - as described above - flow to the container via the transverse bore 45, the annular groove 44, the transverse bore 46 and the line 21. If the flap 27 is folded up for the purpose of connecting a line to the coupling 17, the control slide 41 interrupts the connection between the two transverse bores 45, 46.

Das Ausführungsbeispiel nach Figur 4 zeigt eine Abwandlung desjenigen nach den Figuren 2 und 3. Hier legt sich unter der Kraft der Feder 43 ein Stößel 50 gegen die Klappe 27. Der Stößel hat in seinem in der Sackbohrung 40 liegenden Teil einen kegeligen Bereich 51 sowie einen auf diesen folgenden zylindrischen Bereich 52, an welchen sich dann, wenn die Klappe 27 geschlossen ist der Stößel 53 eines Sitzventils 54 anlegt. In diesem Betriebszustand ist das Sitzventil geöffnet. Nach dem Öffnen der Klappe zwecks Anschließen einer Leitung an die Kupplung 17 gelangt der Stößel 53 an das Ende des kegeligen Bereichs 51, wodurch das Sitzventil 54 geschlossen wird. In diesem Zustand kann kein Druckmittel von der Leitung 18 zur Leitung 21 fließen, so wie es eingangs beschrieben ist.The embodiment according to FIG. 4 shows a modification of that according to FIGS. 2 and 3. Here, under the force of the spring 43, a plunger 50 lies against the flap 27. The plunger has a conical region 51 and a part in the part lying in the blind bore 40 on this following cylindrical region 52, against which, when the flap 27 is closed, the tappet 53 of a seat valve 54 bears. The seat valve is open in this operating state. After the flap has been opened for the purpose of connecting a line to the coupling 17, the tappet 53 reaches the end of the conical region 51, as a result of which the seat valve 54 is closed. In this state, no pressure medium can flow from line 18 to line 21, as described at the beginning.

Claims (5)

1. Hydraulic unit having a single-acting or doubleacting operating cylinder (26), to which the pressure medium delivered by a pump (10) from a container (11) can be supplied via a multi-directional control valve (13) and line couplings (17, 19), arranged in the output lines (16, 18) of the multi-directional control valve (13) downstream from the latter, as well as via supply lines (24, 31) which can be connected to the line couplings (17, 19); characterized in that one of the line couplings (19), when the supply line (31) is uncoupled, can be closed by means of a flap (27) which is in active connection with a control valve (20), and that, via the control valve (20) and as a function of the positioning of the flap, a connection (12, 18, 21) can be made to the container (11) from the pump (10) via the multi-directional control valve (13) and the output line (18) leading to the line coupling (19).
2. Unit according to Claim 1, characterized in that the control valve (20) is a 2/2 directional control valve.
3. Unit according to Claim 1 and/or 2, characterized in that the flap (27) is loaded in the closed position by at least one spring (30, 35, 36).
4. Unit according to one of Claims 1 to 3, characterized in that the control valve (20) is designed as a control slide (41) which sits under spring force (43) with an extension (42) against the flap (27).
5. Unit according to one of Claims 1 to 3, characterized in that the control valve is designed as a seat valve which can be actuated by a plunger sitting against the flap (27) by spring force (43).
EP83102414A 1982-03-23 1983-03-11 Hydraulic system Expired EP0089578B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3210519 1982-03-23
DE19823210519 DE3210519A1 (en) 1982-03-23 1982-03-23 HYDRAULIC SYSTEM

Publications (3)

Publication Number Publication Date
EP0089578A2 EP0089578A2 (en) 1983-09-28
EP0089578A3 EP0089578A3 (en) 1984-09-12
EP0089578B1 true EP0089578B1 (en) 1986-06-11

Family

ID=6158992

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83102414A Expired EP0089578B1 (en) 1982-03-23 1983-03-11 Hydraulic system

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EP (1) EP0089578B1 (en)
DE (2) DE3210519A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE3313039A1 (en) * 1983-04-12 1984-10-18 Robert Bosch Gmbh, 7000 Stuttgart CONTROL DEVICE
DE3833999A1 (en) * 1988-10-06 1990-04-12 Bosch Gmbh Robert HYDRAULIC CONTROL DEVICE

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2954800A (en) * 1960-01-04 1960-10-04 Corson Bros Inc Hydraulic system

Also Published As

Publication number Publication date
DE3364016D1 (en) 1986-07-17
EP0089578A2 (en) 1983-09-28
DE3210519A1 (en) 1983-10-06
EP0089578A3 (en) 1984-09-12

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