DE3419689A1 - Device for supplying pressure medium to a machine, in particular a hydraulic cylinder - Google Patents

Device for supplying pressure medium to a machine, in particular a hydraulic cylinder

Info

Publication number
DE3419689A1
DE3419689A1 DE19843419689 DE3419689A DE3419689A1 DE 3419689 A1 DE3419689 A1 DE 3419689A1 DE 19843419689 DE19843419689 DE 19843419689 DE 3419689 A DE3419689 A DE 3419689A DE 3419689 A1 DE3419689 A1 DE 3419689A1
Authority
DE
Germany
Prior art keywords
hydraulic cylinder
valve
pressure
low
high pressure
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.)
Granted
Application number
DE19843419689
Other languages
German (de)
Other versions
DE3419689C2 (en
Inventor
Gerhard 7000 Stuttgart Mutschler
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.)
Bosch Rexroth AG
Original Assignee
Mannesmann Rexroth AG
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 Mannesmann Rexroth AG filed Critical Mannesmann Rexroth AG
Priority to DE19843419689 priority Critical patent/DE3419689C2/en
Publication of DE3419689A1 publication Critical patent/DE3419689A1/en
Application granted granted Critical
Publication of DE3419689C2 publication Critical patent/DE3419689C2/en
Expired legal-status Critical Current

Links

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
    • 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
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/20—Fluid pressure source, e.g. accumulator or variable axial piston pump
    • F15B2211/205—Systems with pumps
    • F15B2211/20576—Systems with pumps with multiple pumps
    • F15B2211/20592—Combinations of pumps for supplying high and low pressure
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/30505—Non-return valves, i.e. check 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
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/305—Directional control characterised by the type of valves
    • F15B2211/30525—Directional control valves, e.g. 4/3-directional control valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/30—Directional control
    • F15B2211/315—Directional control characterised by the connections of the valve or valves in the circuit
    • F15B2211/31523—Directional control characterised by the connections of the valve or valves in the circuit being connected to a pressure source and an output member
    • F15B2211/31529—Directional control characterised by the connections of the valve or valves in the circuit being connected to a pressure source and an output member having a single pressure source and a single output member
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/405—Flow control characterised by the type of flow control means or valve
    • F15B2211/40507—Flow control characterised by the type of flow control means or valve with constant throttles or orifices
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/40—Flow control
    • F15B2211/415—Flow control characterised by the connections of the flow control means in the circuit
    • F15B2211/41509—Flow control characterised by the connections of the flow control means in the circuit being connected to a pressure source and a directional control valve
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F15—FLUID-PRESSURE ACTUATORS; HYDRAULICS OR PNEUMATICS IN GENERAL
    • F15B—SYSTEMS ACTING BY MEANS OF FLUIDS IN GENERAL; FLUID-PRESSURE ACTUATORS, e.g. SERVOMOTORS; DETAILS OF FLUID-PRESSURE SYSTEMS, NOT OTHERWISE PROVIDED FOR
    • F15B2211/00—Circuits for servomotor systems
    • F15B2211/70—Output members, e.g. hydraulic motors or cylinders or control therefor
    • F15B2211/775—Combined control, e.g. control of speed and force for providing a high speed approach stroke with low force followed by a low speed working stroke with high force, e.g. for a hydraulic press

Abstract

In machines with large pressure differences between the working feed and the rapid-traverse motion, a two-circuit control system with a high-pressure pump and a low-pressure pump is provided. The change-over from working feed to rapid-traverse motion or vice versa is effected by a proportional directional control valve which is constantly attached to the high-pressure and low-pressure line via a restrictor or a non-return valve. The cost can thereby be substantially reduced. <IMAGE>

Description

BESCHREIBUNGDESCRIPTION

Die Erfindung betrifft eine Vorrichtung mit den im Oberbegriff des Patentanspruchs angeführten Merkmalen.The invention relates to a device with the in the preamble of Claim cited features.

Bei einer derartigen bekannten Vorrichtung ist ein Hydrozylinder über ein Mehrwegeventil an die Niederdruckpumpe und parallel hierzu über ein weiteres Mehrwegeventil an die Hochdruckpumpe angeschlossen. Von dem Mehrwegeventil wird die Bewegungsrichtung des Hydrozylinders gesteuert, während die Geschwindigkeit für den Arbeitsvorschub bzw.die Eilgangsbewegung über einstellbare Drosseln zwischen dem jeweiligen Wegeventil und dem Hydrozylinder gewählt wird. Abgesehen von dem verhältnismäßig großen Geräteaufwand muß zum Umschalten der Eilgangsbewegung auf den Arbeitsvorschub das eine Wegeventil gesperrt und das andere Wegeventil in Schaltstellung gebracht werden, wobei sich das unter Hochdruck stehende Druckmittel mit einem Expansionsschlag in die vorher mit Niederdruck beaufschlagte Rohrleitung zum Hydrozylinder entspannt. Dies führt zu starken Schwingungen der Maschine, zu extremer Belastung der Rohrleitungen und einer erheblichen Geräuschbelästigung.In such a known device, a hydraulic cylinder is over a multi-way valve to the low pressure pump and parallel to this via another Multi-way valve connected to the high pressure pump. From the multi-way valve the direction of movement of the hydraulic cylinder is controlled while the speed for the work feed or the rapid traverse movement via adjustable throttles between the respective directional control valve and the hydraulic cylinder is selected. Except for the relatively large equipment must be used to switch the rapid traverse the working feed, one directional valve is blocked and the other directional valve is in the switching position are brought, with the high pressure pressure medium with an expansion stroke expanded into the pipeline to the hydraulic cylinder, which was previously subjected to low pressure. This leads to strong vibrations in the machine and extreme stress on the pipelines and a significant amount of noise.

Der Erfindung liegt somit die Aufgabe zugrunde, die Vorrichtung der eingangs geschilderten Art so auszubilden, daß ein weiches Umschalten von Eilgang auf Arbeitsvorschub ermöglicht und der Geräteaufwand verringert ist.The invention is therefore based on the object of the to train the type described in such a way that a smooth switch from rapid traverse allows to work feed and the equipment effort is reduced.

Erfindungsgemäß ist diese Aufgabe durch die im kennzeichnenden Teil des Patentanspruchs angeführten Merkmale gelöst.According to the invention, this object is due to the in the characterizing part of the claim cited features solved.

Erfindungsgemäß werden die schädlichen Expansionsschläge vermieden und ein weicher Übergang beim Schalten von Niederdruck auf Hochdruck erreicht. Ferner ist die erfindungsgemäße Vorrichtung sehr einfach aufgebaut.According to the invention, the harmful expansion blows are avoided and a smooth transition when switching from Low pressure to high pressure achieved. Furthermore, the device according to the invention has a very simple structure.

Ein Ausführungsbeispiel der Erfindung ist nachstehend anhand der Zeichnung erläutert, in deren einziger Figur ein hydraulischer Schaltplan der Vorrichtung dargestellt ist.An embodiment of the invention is shown below with reference to the drawing explained, in the single figure a hydraulic circuit diagram of the device is shown.

Ein Hydrozylinder 10, der wahlweise eine Eilgangsbewegung oder einen Arbeitsgang mit langsamem Vorschub ausführen soll,ist über Leitungen 11 und 12 mit den Arbeitsanschlüssen A und B eine Wege-Proportionalventils 15 verbunden. Der Anschluß P des Proportionalventils 15 ist über eine Drossel 16 mit einer Hochdruckleitung HD und über ein Rückschlagventil 17 mit einer Niederdruckleitung Nd verbunden. Die Hochdruckleitung ist an eine nicht dargestellte Hochdruckpumpe und die Niederdruckleitung mit einer nicht dargestellten Niederdruckpumpe verbunden. Der Anschluß T des Proportionalventils 15 ist über ein Rückschlagventil 18 mit einem Reservoir T verbunden.A hydraulic cylinder 10, either a rapid traverse or a The operation is to be carried out at a slow feed rate is via lines 11 and 12 with A directional proportional valve 15 is connected to the working connections A and B. The connection P of the proportional valve 15 is via a throttle 16 with a high pressure line HD and connected via a check valve 17 to a low-pressure line Nd. the The high-pressure line is connected to a high-pressure pump (not shown) and the low-pressure line connected to a low pressure pump, not shown. Port T of the proportional valve 15 is connected to a reservoir T via a check valve 18.

In der dargestellten Schaltstellung des Proportionalventils 15 sind die Arbeitsanschlüsse A und B abgesperrt.In the illustrated switching position of the proportional valve 15 are working connections A and B are blocked.

Ausgehend von dieser Neutralstellung kann durch Erregen eines der beiden Elektromagneten des Ventils entweder der Anschluß A mit P bzw. B mit T oder der Anschluß B mit P und A mit T verbunden werden. Abhängig vom Eingangsstrom des Magneten ergibt sich ein bestimmter Durchfluß.Starting from this neutral position, one of the two electromagnets of the valve either the connection A with P or B with T or connection B with P and A with T. Depending on the input current of the Magnets result in a certain flow.

Die Funktionsweise ist folgende: Am P-Anschluß des Proportional-Wegeventils 15 steht der Hochdruck über die Blende 16 an und hält das Rückschlagventil 17 zum Niederdruck ND geschlossen.The mode of operation is as follows: At the P connection of the proportional directional control valve 15 is the high pressure on the orifice 16 and holds the check valve 17 to Low pressure LP closed.

Soll die Eilgangsbewegung erfolgen, so wird das Proportionalventil geöffnet. Der Hochdruck am P-Anschluß baut sich über das Ventil langsam zum Hydrozylinder 10 hin ab. Dann fließt Druckmittel über das Rückschlagventil 17 aus der Niederdruckleitung Nu'und aus der Hochdruckleitung HD über die Drossel 16 zum Hydrozylinder 10, der also mit niedrigem Druck die Eilgangsbewegung ausführt. Es wird der Hochdruck an der Drossel 16 auf das Niveau des Niederdrucks abgebaut.If the rapid traverse movement is to take place, the proportional valve is opened. The high pressure at the P connection builds up slowly through the valve to the hydraulic cylinder 10 down. Pressure medium then flows through the check valve 17 from the low-pressure line Nu'und from the high pressure line HD via the throttle 16 to the hydraulic cylinder 10, the thus executes the rapid traverse movement with low pressure. It gets the high pressure on the throttle 16 is reduced to the level of the low pressure.

Soll nun der Arbeitsvorschub mit hohem Druck erfolgen, so wird das Proportionalventil 15 so angesteuert, daß sich der Durchflußquerschnitt durch das Proportionalventil auf Vorschubgeschwindigkeit, nämlich auf den Querschnitt der Drossel 16 verkleinert. Damit baut sich am P-Anschluß des Proportionalventils 15 der Hochdruck HD auf, der dem Hydrozylinder 10 zur Verfügung steht, worauf dieser den Arbeitsvorschub ausführt.If the work feed is now to take place at high pressure, this will be Proportional valve 15 controlled so that the flow cross-section through the Proportional valve on the feed rate, namely on the cross section of the Reduced throttle 16. This builds up at the P connection of the proportional valve 15 the high pressure HD, which is available to the hydraulic cylinder 10, whereupon this executes the work feed.

Es ist leicht erkennbar, daß die Einstellung des Proportionalventils auf den jeweiligen, für den Eilgang und den Arbeitsvorschub erforderlichen Durchflußquerschnitt einen weichen Ubergang von Nieder- auf Hochdruck ermöglicht, so daß starke plötzliche Druckunterschiede vermieden sind. Auch der Geräteaufwand ist erheblich verringert.It is easy to see that the setting of the proportional valve to the respective flow cross-section required for the rapid traverse and the work feed allows a smooth transition from low to high pressure, so that strong sudden changes Differences in pressure are avoided. The outlay on equipment is also considerably reduced.

Claims (1)

PATENTANSPRUCH Vorrichtung zur Druckmittelversorgung einer Maschine, insbesondere eines Hydrozylinders mit Niederdruck zur Ausführung eines Eilgangs und mit Hochdruck zur Ausführung eines Arbeitsvorschubes, wobei die Bewegungsrichtung von einem Mehrwegeventil und die Hubgeschwindigkeit an einer Drosselöffnung einstellbar ist, dadurch gekennzeichnet, daß der Hydrozylinder (10) über ein Wege-Proportionalventil (15) und ein in Reihe mit dem Wegeproportionalventil liegendes Rückschlagventil (17) an die Niederdruckleitung und über eine mit dem Proportionalventil in Reihe liegende Drossel (16) mit der Hochdruckleitung verbunden ist.PATENT CLAIM Device for supplying pressure medium to a machine, in particular a hydraulic cylinder with low pressure for executing a rapid traverse and with high pressure to execute a work feed, the direction of movement adjustable by a multi-way valve and the lifting speed at a throttle opening is, characterized in that the hydraulic cylinder (10) has a directional proportional valve (15) and a check valve in series with the directional proportional valve (17) to the low pressure line and via one in series with the proportional valve lying throttle (16) is connected to the high pressure line.
DE19843419689 1984-05-25 1984-05-25 Device for supplying pressure medium to a hydraulic cylinder Expired DE3419689C2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
DE19843419689 DE3419689C2 (en) 1984-05-25 1984-05-25 Device for supplying pressure medium to a hydraulic cylinder

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
DE19843419689 DE3419689C2 (en) 1984-05-25 1984-05-25 Device for supplying pressure medium to a hydraulic cylinder

Publications (2)

Publication Number Publication Date
DE3419689A1 true DE3419689A1 (en) 1985-11-28
DE3419689C2 DE3419689C2 (en) 1986-11-27

Family

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Family Applications (1)

Application Number Title Priority Date Filing Date
DE19843419689 Expired DE3419689C2 (en) 1984-05-25 1984-05-25 Device for supplying pressure medium to a hydraulic cylinder

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DE (1) DE3419689C2 (en)

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2521533A1 (en) * 1974-05-16 1975-11-27 Poclain Sa ACTUATION SHIFT WITH PRESSURIZED FLUID
DE2021182C3 (en) * 1970-04-30 1978-03-30 Maschinenfabrik Weingarten Ag, 7987 Weingarten Device for setting the plunger speeds and pressures in die-casting machines with a three-phase system, especially in cold-chamber die-casting machines
DE2747548A1 (en) * 1977-10-22 1979-04-26 Thyssen Industrie SERVOHYDRAULIC PRESS WITH GE CLOSED LOOP
DE2809387A1 (en) * 1978-03-04 1980-01-17 Thyssen Industrie HYDRAULIC CUTTING, BURRING OR THE LIKE. -PRESS WITH HIGHLY CHANGE MOVEMENT RESISTANCE OF THE PRESS SLIDE DURING THE SLIDE PATH
DE2919206A1 (en) * 1979-05-12 1980-11-20 Bosch Gmbh Robert DEVICE FOR CONTROLLING A HYDRAULIC CONSUMER
EP0029223A2 (en) * 1979-11-15 1981-05-27 Politechnika Krakowska Hydraulic service system for a pulsating press
DE3235954A1 (en) * 1982-09-29 1984-03-29 Mannesmann Rexroth GmbH, 8770 Lohr Device for controlling a machine tool slide

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2021182C3 (en) * 1970-04-30 1978-03-30 Maschinenfabrik Weingarten Ag, 7987 Weingarten Device for setting the plunger speeds and pressures in die-casting machines with a three-phase system, especially in cold-chamber die-casting machines
DE2521533A1 (en) * 1974-05-16 1975-11-27 Poclain Sa ACTUATION SHIFT WITH PRESSURIZED FLUID
DE2747548A1 (en) * 1977-10-22 1979-04-26 Thyssen Industrie SERVOHYDRAULIC PRESS WITH GE CLOSED LOOP
DE2809387A1 (en) * 1978-03-04 1980-01-17 Thyssen Industrie HYDRAULIC CUTTING, BURRING OR THE LIKE. -PRESS WITH HIGHLY CHANGE MOVEMENT RESISTANCE OF THE PRESS SLIDE DURING THE SLIDE PATH
DE2919206A1 (en) * 1979-05-12 1980-11-20 Bosch Gmbh Robert DEVICE FOR CONTROLLING A HYDRAULIC CONSUMER
EP0029223A2 (en) * 1979-11-15 1981-05-27 Politechnika Krakowska Hydraulic service system for a pulsating press
DE3235954A1 (en) * 1982-09-29 1984-03-29 Mannesmann Rexroth GmbH, 8770 Lohr Device for controlling a machine tool slide

Non-Patent Citations (5)

* Cited by examiner, † Cited by third party
Title
AT-Fachbuch: H. Zoebl, "Ölhydraulik", Wien, Springer-Verlag, 1963, Seite 325 *
Der Hydraulik-Trainer, Lehr- und Informations- buch über Hydraulik, 2. Auflage 11.80, G.L. Rexroth gmbH, S. 144 *
H. Berd, Hydraulische Eilgang- und Vorschub- steuerungen in Blockverkettung, in: Werkstatt und Betrieb 113 (1980)5, S. 323-325 *
Herion Information, Schrittmascher der Auto- mation, 3/1969, S. 14 u. 15 *
K. Kasperbauer, Wirkungsweise und konstruktive Besonderheiten von Proportionalventilen, in: Maschinenmarkt, Würzburg 88(1982)57, S. 1177-1180 *

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Publication number Publication date
DE3419689C2 (en) 1986-11-27

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8363 Opposition against the patent
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