EP0667459A1 - Electro-proportional solenoid-valve unit - Google Patents

Electro-proportional solenoid-valve unit Download PDF

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Publication number
EP0667459A1
EP0667459A1 EP95100336A EP95100336A EP0667459A1 EP 0667459 A1 EP0667459 A1 EP 0667459A1 EP 95100336 A EP95100336 A EP 95100336A EP 95100336 A EP95100336 A EP 95100336A EP 0667459 A1 EP0667459 A1 EP 0667459A1
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EP
European Patent Office
Prior art keywords
piston
valve unit
electromagnet
hydraulic
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.)
Granted
Application number
EP95100336A
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German (de)
French (fr)
Other versions
EP0667459B1 (en
Inventor
Bernd Niethammer
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.)
HYDRAULIK-RING ANTRIEBS- und STEUERUNGSTECHNIK GmbH
Hilite Germany GmbH
Original Assignee
HYDRAULIK-RING ANTRIEBS- und STEUERUNGSTECHNIK GmbH
Hydraulik Ring GmbH
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Publication of EP0667459A1 publication Critical patent/EP0667459A1/en
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Publication of EP0667459B1 publication Critical patent/EP0667459B1/en
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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
    • F15B13/044—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by electrically-controlled means, e.g. solenoids, torque-motors
    • F15B13/0442—Fluid distribution or supply devices characterised by their adaptation to the control of servomotors for use with a single servomotor operated by electrically-controlled means, e.g. solenoids, torque-motors with proportional solenoid allowing stable intermediate positions
    • 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
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/86493—Multi-way valve unit
    • Y10T137/86574—Supply and exhaust
    • Y10T137/86622—Motor-operated
    • 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
    • Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
    • Y10T137/00—Fluid handling
    • Y10T137/8593—Systems
    • Y10T137/86493—Multi-way valve unit
    • Y10T137/86574—Supply and exhaust
    • Y10T137/8667—Reciprocating valve
    • Y10T137/86694—Piston valve
    • Y10T137/86702—With internal flow passage

Definitions

  • the invention relates to an electro-proportional solenoid valve unit according to the preamble of claim 1.
  • the piston which is designed as a hollow piston, is displaced against the force of a compression spring.
  • the one working connection to the unit to be actuated is opened so that the hydraulic medium can flow to the unit via this opened working connection.
  • the hydraulic medium displaced from this unit reaches the other working connection and from there into the cavity of the piston. From there, the hydraulic medium flows back to the tank.
  • a hydraulic dynamic pressure which is greater than the pressure acting on the opposite piston side, forms in one hydraulic chamber depending on the volume of the hydraulic medium which flows through the diameter-limited cavity of the piston.
  • the invention has for its object to design the generic electro-proportional solenoid valve unit so that the flow rate of the hydraulic medium changes depending on the current with which the electromagnet is applied, constantly changing.
  • the hydraulic chamber located in the electromagnet is separated from the adjacent annular channel of the piston and its cavity.
  • hydraulic dynamic pressure cannot build up in this hydraulic space.
  • the piston is in the appropriate position, the hydraulic medium coming from the unit to be controlled reaches the annular channel and from there via the opening into the cavity of the piston.
  • This cavity is separated from the hydraulic space so that the displaced medium cannot get into this hydraulic space.
  • a hydraulic back pressure in this hydraulic space is thus avoided in a structurally simple manner.
  • the flow rate-current characteristic of this valve unit changes continuously to the desired extent, and there is no sudden change in the flow rate. This ensures that the aggregate to be controlled or regulated is reliably actuated over the entire course of the characteristic curve.
  • the drawing shows partly in longitudinal section and partly in view an electro-proportional solenoid valve unit according to the invention.
  • the piston of the valve unit is shown in its initial position and in the lower half in a position displaced by a plunger of an electromagnet.
  • the electro-proportional solenoid valve unit has an electromagnet 1, the plunger 2 of which bears against a piston 3. It is under the force of a compression spring 4, which presses the piston 3 against the plunger 2.
  • the electromagnet 1 is designed in a known manner so that it is not described in detail. It is attached to an installation housing 5, which has a receptacle 6 for a valve housing 7.
  • the piston 3 is mounted in a longitudinally displaceable manner in it.
  • the valve housing 7 has connections 8 to 10, via which, controlled by the piston 3, hydraulic medium is conveyed to or from a consumer in a known manner.
  • the corresponding consumer and the tank containing the hydraulic medium are also connected to the installation housing 5 in a known manner.
  • the compression spring 4 is supported on an adjusting screw 11 screwed into the valve housing 7.
  • the prestressing force of the compression spring 4 and thus the position of the piston 3 relative to the magnetic force can be adjusted continuously by screwing the adjusting screw 11 into the valve housing 7 to different degrees.
  • the adjusting screw 11 has a through opening through which the hydraulic medium can flow back to the tank.
  • the piston 3 is provided on its side facing the adjusting screw 11 with a recess 12, on the bottom 13 of which the compression spring 4 is supported.
  • the piston has a central bore 14 which extends in its axial direction and which is closed by a base 15 in the direction of the plunger 2 of the electromagnet 1.
  • the tappet 2 of the electromagnet 1 bears against this base 15.
  • An opening 16 opens radially into the bore 14 of the piston 3, through which the hydraulic medium can get into the bore 14 of the piston 3.
  • the outside of the piston has an annular channel 17 which is closed against the electromagnet 1 by an annular web 18.
  • the piston 3 has a further ring channel 19 which is considerably longer than the ring channel 17 and which is separated from this ring channel 17 by an annular web 20.
  • the working connection 10 is open to a hydraulic chamber 21 in which the compression spring 4 lies and into which the central bore 14 of the piston 3 opens.
  • the central bore 14 is connected to the annular channel 17 of the piston 3, into which the opening 16 opens.
  • the working connection 8 is also connected to the annular channel 19 of the piston 3. Since the connection 9, which is connected to the (not shown) pump of the hydraulic system via a connection 27 of the installation housing 5, is also connected to the ring channel 19, a connection between the working connection 8 and the pressure connection 9 is thus present.
  • the other working connection 10 of the valve housing 7 is not closed in this left end position of the piston 3, so that there is a connection to the hydraulic chamber 21.
  • the piston 3 in the left end position, the piston 3 is at a distance from the bottom 22 of the valve housing 7. As a result, a further hydraulic chamber 23 is formed between the piston 3 and the bottom 22, which has at least one bore 24 axially penetrating through the piston 3 must not come into connection with the opening 16, is connected to the opposite hydraulic chamber 21.
  • the piston 3 has a further bore 25 which penetrates it axially and which connects the two hydraulic chambers 21 and 23 to one another.
  • a unit to be controlled or regulated by means of the valve unit for example a piston-cylinder unit, is connected to the connections 8 and 10 of the valve housing 7. If this unit is to be actuated, the electromagnet 1 is switched on, whereby the plunger 2 is extended. It displaces the piston 3 against the force of the compression spring 4. When the piston 3 is moved, the connection between the pressure connection 9 and the working connection 8 is closed, while the connection between the working connection 10 and the pressure connection 9 is opened.
  • the pressurized hydraulic medium can flow via the pressure connection 9 and the ring channel 19 to the working connection 10, from which it flows via a connection 28 of the installation housing 5 to the unit to be driven and actuate it in the desired manner.
  • the hydraulic medium displaced from the unit to be driven can get back to the tank via the working connection 8, the annular channel 17, the opening 16, the bore 14 of the piston 3, the hydraulic chamber 21 and the through opening of the adjusting screw 11.
  • the control electronics recognize that the position of the actuating unit of the unit to be driven has been reached, the control current is reduced.
  • the magnetic force is reduced and the piston 3 is returned under the force of the compression spring 5 to a central position in which the two ring webs 20 and 26 of the piston 3 close the two connections 8 and 10. This maintains the hydraulic pressure in the unit to be driven.
  • the piston 3 is returned under the force of the compression spring 4 to its end position on the left in the drawing, the plunger 2 being pushed back into the housing of the electromagnet 1 accordingly.
  • the connection between the connection 10 and the pressure connection 9 is closed, while the connection between the connection 8 and the pressure connection 9 is opened by the piston 3.
  • the pressurized hydraulic medium can reach the piston of the unit to be driven via the connection 10 and push this piston back again.
  • the bores 24, 25 have a smaller cross section than the central bore 14.
  • the bores 14 and 24, 25 can also have the same diameter. It is also possible that the compensating bores 24, 25 have a larger diameter than the central bore 14 of the piston 3.
  • the hydraulic medium displaced via the connection 8 from the unit to be driven can only flow back via this ring channel 17 and the opening 16 into the bore 14 of the piston 3 and from there to the tank.
  • the central bore 14 of the piston 3 is separated from the hydraulic chamber 23 by the base 15.

Abstract

The proportional electromagnetically actuated fluid power valve has a main housing sleeve (7) that supports a hollow cylindrical spool (3) that has formed ring shaped flow channels (17,19). The spool is displaced axially by the armature pin (2) of the actuator (1). Flow passes through the channels to control the flow between inlet and outlet (8,10) ports. The ring channel (17) is coupled to a central region in a tube (14) by a port (16) and this avoids hydraulic stagnation pressure being generated to modify the proportional action of the valve.

Description

Die Erfindung betrifft eine Elektroproportionalmagnet-Ventileinheit nach dem Oberbegriff des Anspruches 1.The invention relates to an electro-proportional solenoid valve unit according to the preamble of claim 1.

Wird der Elektromagnet bei dieser bekannten Ventileinheit erregt, dann wird der als Hohlkolben ausgebildete Kolben gegen die Kraft einer Druckfeder verschoben. Dabei wird der eine Arbeitsanschluß zum zu betätigenden Aggregat geöffnet, so daß das Hydraulikmedium über diesen geöffneten Arbeitsanschluß zum Aggregat strömen kann. Das aus diesem Aggregat verdrängte Hydraulikmedium gelangt zum anderen Arbeitsanschluß und von dort in den Hohlraum des Kolbens. Von dort aus strömt das Hydraulikmedium zum Tank zurück. Auf der dem Elektromagneten zugewandten Kolbenseite bildet sich in dem einen Hydraulikraum in Abhängigkeit des Volumens des Hydraulikmediums, welches durch den im Durchmesser begrenzten Hohlraum des Kolbens fließt, ein hydraulischer Staudruck, der größer ist als der Druck, der auf die gegenüberliegende Kolbenseite wirkt. Dadurch ändert sich mit zunehmender Stromstärke, mit welcher der Elektromagnet die beteiligten Steuerkanten beaufschlagt, die Lage des Kolbens und der Durchfluß des Hydraulikmediums. Sobald ein kritischer Durchflußwert überschritten wird, tritt infolge der wirkenden Druckkräfte auf der Magnetseite des Kolbens, die sich zu den Magnetkräften addieren, eine schlagartige Veränderung der Kolbenposition ein. Unterhalb dieses kritischen Durchflußwertes verläuft die Durchfluß-Strom-Kennlinie noch im gewünschten Maß. Oberhalb dieses kritischen Durchflußwertes tritt jedoch eine unerwünschte schlagartige Änderung des Durchflußvolumens auf.If the electromagnet is excited in this known valve unit, the piston, which is designed as a hollow piston, is displaced against the force of a compression spring. The one working connection to the unit to be actuated is opened so that the hydraulic medium can flow to the unit via this opened working connection. The hydraulic medium displaced from this unit reaches the other working connection and from there into the cavity of the piston. From there, the hydraulic medium flows back to the tank. On the piston side facing the electromagnet, a hydraulic dynamic pressure, which is greater than the pressure acting on the opposite piston side, forms in one hydraulic chamber depending on the volume of the hydraulic medium which flows through the diameter-limited cavity of the piston. As a result, the position of the piston and the flow of the hydraulic medium change with increasing current intensity with which the electromagnet acts on the control edges involved. As soon as a critical flow value is exceeded, an abrupt change in the piston position occurs as a result of the pressure forces acting on the magnetic side of the piston, which add up to the magnetic forces. Below this critical flow value, the flow-current characteristic curve still runs to the desired extent. Above this critical flow value, however, an undesirable sudden change in the flow volume occurs.

Der Erfindung liegt die Aufgabe zugrunde, die gattungsgemäße Elektroproportionalmagnet-Ventileinheit so auszubilden, daß sich die Durchflußmenge des Hydraulikmediums in Abhängigkeit von der Stromstärke, mit welcher der Elektromagnet beaufschlagt wird, stetig verändert.The invention has for its object to design the generic electro-proportional solenoid valve unit so that the flow rate of the hydraulic medium changes depending on the current with which the electromagnet is applied, constantly changing.

Diese Aufgabe wird bei der gattungsgemäßen Elektroproportionalmagnet-Ventileinheit erfindungsgemäß mit den kennzeichnenden Merkmalen des Anspruches 1 gelöst.This object is achieved in the generic electro-proportional solenoid valve unit according to the invention with the characterizing features of claim 1.

Bei der erfindungsgemäßen Ventileinheit ist der beim Elektromagneten liegende Hydraulikraum vom benachbarten Ringkanal des Kolbens und dessen Hohlraum getrennt. Dadurch kann sich in diesem Hydraulikraum ein hydraulischer Staudruck nicht bilden. Das vom zu steuernden Aggregat kommende Hydraulikmedium gelangt bei entsprechender Stellung des Kolbens in den Ringkanal und von dort über die Öffnung in den Hohlraum des Kolbens. Dieser Hohlraum ist gegenüber dem Hydraulikraum abgetrennt, so daß das verdrängte Medium nicht in diesen Hydraulikraum gelangen kann. Somit wird in konstruktiv einfacher Weise ein hydraulischer Staudruck in diesem Hydraulikraum vermieden. Dadurch ändert sich die Durchflußmenge-Strom-Kennlinie dieser Ventileinheit in gewünschtem Maße stetig, und es tritt eine schlagartige Änderung der Durchflußmenge nicht auf. Dadurch ist sichergestellt, daß über den gesamten Kennlinienverlauf das zu steuernde oder zu regelnde Aggregat zuverlässig betätigt wird.In the valve unit according to the invention, the hydraulic chamber located in the electromagnet is separated from the adjacent annular channel of the piston and its cavity. As a result, hydraulic dynamic pressure cannot build up in this hydraulic space. When the piston is in the appropriate position, the hydraulic medium coming from the unit to be controlled reaches the annular channel and from there via the opening into the cavity of the piston. This cavity is separated from the hydraulic space so that the displaced medium cannot get into this hydraulic space. A hydraulic back pressure in this hydraulic space is thus avoided in a structurally simple manner. As a result, the flow rate-current characteristic of this valve unit changes continuously to the desired extent, and there is no sudden change in the flow rate. This ensures that the aggregate to be controlled or regulated is reliably actuated over the entire course of the characteristic curve.

Weitere Merkmale der Erfindung ergeben sich aus den weiteren Ansprüchen, der Beschreibung und der Zeichnung.Further features of the invention result from the further claims, the description and the drawing.

Die Erfindung wird anhand eines in der Zeichnung dargestellten Ausführungsbeispieles näher erläutert. Die Zeichnung zeigt teilweise im Längsschnitt und teilweise in Ansicht eine erfindungsgemäße Elektroproportionalmagnet-Ventileinheit. In der oberen Hälfte der Zeichnung ist der Kolben der Ventileinheit in seiner Ausgangsstellung und in der unteren Hälfte in einer durch einen Stößel eines Elektromagneten verschobenen Lage dargestellt.The invention is explained in more detail using an exemplary embodiment shown in the drawing. The drawing shows partly in longitudinal section and partly in view an electro-proportional solenoid valve unit according to the invention. In the upper half of the drawing, the piston of the valve unit is shown in its initial position and in the lower half in a position displaced by a plunger of an electromagnet.

Die Elektroproportionalmagnet-Ventileinheit hat einen Elektromagneten 1, dessen Stößel 2 an einem Kolben 3 anliegt. Er steht unter der Kraft einer Druckfeder 4, welche den Kolben 3 gegen den Stößel 2 drückt.The electro-proportional solenoid valve unit has an electromagnet 1, the plunger 2 of which bears against a piston 3. It is under the force of a compression spring 4, which presses the piston 3 against the plunger 2.

Der Elektromagnet 1 ist in bekannter Weise ausgebildet, so daß er nicht im einzelnen beschrieben wird. Er ist an einem Einbaugehäuse 5 befestigt, das eine Aufnahme 6 für ein Ventilgehäuse 7 aufweist. In ihm ist der Kolben 3 längsverschieblich gelagert. Das Ventilgehäuse 7 hat Anschlüsse 8 bis 10, über die, vom Kolben 3 gesteuert, Hydraulikmedium zu bzw. von einem Verbraucher in bekannter Weise gefördert wird. An das Einbaugehäuse 5 sind der entsprechende Verbraucher sowie der das Hydraulikmedium enthaltende Tank ebenfalls in bekannter Weise angeschlossen.The electromagnet 1 is designed in a known manner so that it is not described in detail. It is attached to an installation housing 5, which has a receptacle 6 for a valve housing 7. The piston 3 is mounted in a longitudinally displaceable manner in it. The valve housing 7 has connections 8 to 10, via which, controlled by the piston 3, hydraulic medium is conveyed to or from a consumer in a known manner. The corresponding consumer and the tank containing the hydraulic medium are also connected to the installation housing 5 in a known manner.

Die Druckfeder 4 stützt sich an einer in das Ventilgehäuse 7 geschraubten Einstellschraube 11 ab. Durch unterschiedlich weites Einschrauben der Einstellschraube 11 in das Ventilgehäuse 7 läßt sich die Vorspannkraft der Druckfeder 4 und somit die Lage des Kolbens 3 zur Magnetkraft stufenlos einstellen. Die Einstellschraube 11 hat eine Durchgangsöffnung, über die das Hydraulikmedium zum Tank zurückströmen kann.The compression spring 4 is supported on an adjusting screw 11 screwed into the valve housing 7. The prestressing force of the compression spring 4 and thus the position of the piston 3 relative to the magnetic force can be adjusted continuously by screwing the adjusting screw 11 into the valve housing 7 to different degrees. The adjusting screw 11 has a through opening through which the hydraulic medium can flow back to the tank.

Der Kolben 3 ist an seiner der Einstellschraube 11 zugewandten Seite mit einer Vertiefung 12 versehen, an deren Boden 13 sich die Druckfeder 4 abstützt. Der Kolben hat eine zentrale, in seiner Achsrichtung sich erstreckende Bohrung 14, die in Richtung auf den Stößel 2 des Elektromagneten 1 durch einen Boden 15 geschlossen ist. An diesem Boden 15 liegt der Stößel 2 des Elektromagneten 1 an. In die Bohrung 14 des Kolbens 3 mündet radial eine Öffnung 16, durch welche das Hydraulikmedium in die Bohrung 14 des Kolbens 3 gelangen kann.The piston 3 is provided on its side facing the adjusting screw 11 with a recess 12, on the bottom 13 of which the compression spring 4 is supported. The piston has a central bore 14 which extends in its axial direction and which is closed by a base 15 in the direction of the plunger 2 of the electromagnet 1. The tappet 2 of the electromagnet 1 bears against this base 15. An opening 16 opens radially into the bore 14 of the piston 3, through which the hydraulic medium can get into the bore 14 of the piston 3.

Der Kolben weist außenseitig einen Ringkanal 17 auf, der gegen den Elektromagneten 1 durch einen Ringsteg 18 geschlossen ist. Der Kolben 3 weist einen weiteren Ringkanal 19 auf, der wesentlich länger ist als der Ringkanal 17 und der gegenüber diesem Ringkanal 17 durch einen Ringsteg 20 getrennt ist.The outside of the piston has an annular channel 17 which is closed against the electromagnet 1 by an annular web 18. The piston 3 has a further ring channel 19 which is considerably longer than the ring channel 17 and which is separated from this ring channel 17 by an annular web 20.

In der in der oberen Hälfte der Zeichnung dargestellten linken Endstellung des Kolbens 3 ist der Arbeitsanschluß 10 zu einem Hydraulikraum 21 offen, in dem die Druckfeder 4 liegt und in den die zentrale Bohrung 14 des Kolbens 3 mündet. Über die radial verlaufende Öffnung 16 ist die zentrale Bohrung 14 mit dem Ringkanal 17 des Kolbens 3 verbunden, in den die Öffnung 16 mündet. In dieser linken Endstellung des Kolbens 3 ist außerdem der Arbeitsanschluß 8 mit dem Ringkanal 19 des Kolbens 3 verbunden. Da auch der Anschluß 9, der mit der (nicht dargestellten) Pumpe des Hydrauliksystems über einen Anschluß 27 des Einbaugehäuses 5 verbunden ist, mit dem Ringkanal 19 verbunden ist, ist somit eine Verbindung zwischen dem Arbeitsanschluß 8 und dem Druckanschluß 9 vorhanden. Der andere Arbeitsanschluß 10 des Ventilgehäuses 7 ist in dieser linken Endstellung des Kolbens 3 nicht verschlossen, so daß eine Verbindung zum Hydraulikraum 21 besteht.In the left end position of the piston 3 shown in the upper half of the drawing, the working connection 10 is open to a hydraulic chamber 21 in which the compression spring 4 lies and into which the central bore 14 of the piston 3 opens. Via the radially extending opening 16, the central bore 14 is connected to the annular channel 17 of the piston 3, into which the opening 16 opens. In this left end position of the piston 3, the working connection 8 is also connected to the annular channel 19 of the piston 3. Since the connection 9, which is connected to the (not shown) pump of the hydraulic system via a connection 27 of the installation housing 5, is also connected to the ring channel 19, a connection between the working connection 8 and the pressure connection 9 is thus present. The other working connection 10 of the valve housing 7 is not closed in this left end position of the piston 3, so that there is a connection to the hydraulic chamber 21.

Wie die Zeichnung zeigt, hat der Kolben 3 in der linken Endstellung Abstand vom Boden 22 des Ventilgehäuses 7. Dadurch wird zwischen dem Kolben 3 und dem Boden 22 ein weiterer Hydraulikraum 23 gebildet, der durch mindestens eine den Kolben 3 axial durchsetzende Bohrung 24, die nicht mit der Öffnung 16 in Verbindung kommen darf, mit dem gegenüberliegenden Hydraulikraum 21 verbunden ist. Im dargestellten Ausführungsbeispiel hat der Kolben 3 eine weitere, ihn axial durchsetzende Bohrung 25, welche die beiden Hydraulikräume 21 und 23 miteinander verbindet.As the drawing shows, in the left end position, the piston 3 is at a distance from the bottom 22 of the valve housing 7. As a result, a further hydraulic chamber 23 is formed between the piston 3 and the bottom 22, which has at least one bore 24 axially penetrating through the piston 3 must not come into connection with the opening 16, is connected to the opposite hydraulic chamber 21. In the exemplary embodiment shown, the piston 3 has a further bore 25 which penetrates it axially and which connects the two hydraulic chambers 21 and 23 to one another.

An die Anschlüsse 8 und 10 des Ventilgehäuses 7 ist ein mittels der Ventileinheit zu steuerndes bzw. zu regelndes Aggregat angeschlossen, beispielsweise eine Kolben-Zylinder-Einheit. Soll dieses Aggregat betätigt werden, wird der Elektromagnet 1 eingeschaltet, wodurch der Stößel 2 ausgefahren wird. Er verschiebt den Kolben 3 gegen die Kraft der Druckfeder 4. Beim Verschieben des Kolbens 3 wird die Verbindung zwischen dem Druckanschluß 9 und dem Arbeitsanschluß 8 geschlossen, während die Verbindung zwischen dem Arbeitsanschluß 10 und dem Druckanschluß 9 geöffnet wird. Damit kann das unter Druck stehende Hydraulikmedium über den Druckanschluß 9 und den Ringkanal 19 zum Arbeitsanschluß 10 strömen, von dem es über einen Anschluß 28 des Einbaugehäuses 5 zum anzutreibenden Aggregat strömen und es in der gewünschten Weise betätigen. Das aus dem anzutreibenden Aggregat verdrängte Hydraulikmedium kann über den Arbeitsanschluß 8, den Ringkanal 17, die Öffnung 16, die Bohrung 14 des Kolbens 3, den Hydraulikraum 21 und die Durchgangsöffnung der Einstellschraube 11 zurück zum Tank gelangen. Wenn die Steuerelektronik erkennt, daß die Position der Stelleinheit des anzutreibenden Aggregates erreicht ist, wird der Steuerstrom zurückgefahren. Dadurch wird die Magnetkraft verringert und der Kolben 3 unter der Kraft der Druckfeder 5 in eine Mittelstellung zurückgeführt, in der die beiden Ringstege 20 und 26 des Kolbens 3 die beiden Anschlüsse 8 und 10 verschließen. Dadurch bleibt der Hydraulikdruck im anzutreibenden Aggregat aufrechterhalten.A unit to be controlled or regulated by means of the valve unit, for example a piston-cylinder unit, is connected to the connections 8 and 10 of the valve housing 7. If this unit is to be actuated, the electromagnet 1 is switched on, whereby the plunger 2 is extended. It displaces the piston 3 against the force of the compression spring 4. When the piston 3 is moved, the connection between the pressure connection 9 and the working connection 8 is closed, while the connection between the working connection 10 and the pressure connection 9 is opened. Thus, the pressurized hydraulic medium can flow via the pressure connection 9 and the ring channel 19 to the working connection 10, from which it flows via a connection 28 of the installation housing 5 to the unit to be driven and actuate it in the desired manner. The hydraulic medium displaced from the unit to be driven can get back to the tank via the working connection 8, the annular channel 17, the opening 16, the bore 14 of the piston 3, the hydraulic chamber 21 and the through opening of the adjusting screw 11. When the control electronics recognize that the position of the actuating unit of the unit to be driven has been reached, the control current is reduced. As a result, the magnetic force is reduced and the piston 3 is returned under the force of the compression spring 5 to a central position in which the two ring webs 20 and 26 of the piston 3 close the two connections 8 and 10. This maintains the hydraulic pressure in the unit to be driven.

Wird der Elektromagnet 1 abgeschaltet, wird der Kolben 3 unter der Kraft der Druckfeder 4 wieder in seine in der Zeichnung linke Endstellung zurückgeführt, wobei der Stößel 2 entsprechend in das Gehäuse des Elektromagneten 1 zurückgeschoben wird. Dabei wird die Verbindung zwischen dem Anschluß 10 und dem Druckanschluß 9 geschlossen, während die Verbindung zwischen dem Anschluß 8 und dem Druckanschluß 9 durch den Kolben 3 geöffnet wird. Dadurch kann das unter Druck stehende Hydraulikmedium über den Anschluß 10 zum Kolben des anzutreibenden Aggregates gelangen und diesen Kolben wieder zurückschieben.If the electromagnet 1 is switched off, the piston 3 is returned under the force of the compression spring 4 to its end position on the left in the drawing, the plunger 2 being pushed back into the housing of the electromagnet 1 accordingly. The connection between the connection 10 and the pressure connection 9 is closed, while the connection between the connection 8 and the pressure connection 9 is opened by the piston 3. As a result, the pressurized hydraulic medium can reach the piston of the unit to be driven via the connection 10 and push this piston back again.

Über die beiden Bohrungen 24 und 25 im Kolben 3 wird in einfacher Weise ein Druckausgleich in den beiden Hydraulikräumen 21, 23 zu beiden Seiten des Kolbens 3 erreicht. Dadurch herrscht auf beiden Seiten des Kolbens 3 Druckgleichheit. Das Hydraulikmedium strömt in den beiden Bohrungen 24, 25 des Kolbens 3 praktisch nicht, vielmehr bildet sich hier ein statischer Druck aus. Das vor dem Kolben 3 befindliche Hydraulikmedium wird beim Verschieben des Kolbens über die Bohrungen 24, 25 lediglich verdrängt. Hierbei kann auch eine gewisse Dämpfung des Kolbens 3 bei seiner Verschiebebewegung erreicht werden.Pressure equalization in the two hydraulic chambers 21, 23 on both sides of the piston 3 is achieved in a simple manner via the two bores 24 and 25 in the piston 3. As a result, there is 3 pressure equality on both sides of the piston. The hydraulic medium practically does not flow in the two bores 24, 25 of the piston 3, rather a static pressure is formed here. The hydraulic medium in front of the piston 3 is only displaced through the bores 24, 25 when the piston is moved. Here, a certain damping of the piston 3 during its displacement movement can also be achieved.

Die Bohrungen 24, 25 haben im dargestellten Ausführungsbeispiel kleineren Querschnitt als die zentrale Bohrung 14. Die Bohrungen 14 und 24, 25 können aber auch gleichen Durchmesser haben. Ebenso ist es möglich, daß die Ausgleichsbohrungen 24, 25 größeren Durchmesser als die zentrale Bohrung 14 des Kolbens 3 haben.In the exemplary embodiment shown, the bores 24, 25 have a smaller cross section than the central bore 14. The bores 14 and 24, 25 can also have the same diameter. It is also possible that the compensating bores 24, 25 have a larger diameter than the central bore 14 of the piston 3.

Um die Bohrungen 24, 25 zu erhalten, ist es auch möglich, in den als Hohlkolben ausgebildeten Kolben 3 eine Buchse einzusetzen. In der Außenwandung einer solchen Buchse und/oder in der Innenwandung der Bohrung des Kolbens kann jeweils mindestens eine über die Kolben- bzw. Buchsenlänge durchgehende Vertiefung vorgesehen sein.In order to obtain the bores 24, 25, it is also possible to use a bushing in the piston 3 designed as a hollow piston. In the outer wall of such a bushing and / or in the inner wall of the bore of the piston, at least one recess extending over the length of the piston or bushing can be provided.

Da der Hydraulikraum 23 durch den Ringsteg 18 des Kolbens 3 vom Ringkanal 17 getrennt ist, kann das über den Anschluß 8 aus dem anzutreibenden Aggregat verdrängte Hydraulikmedium nur über diesen Ringkanal 17 und die Öffnung 16 in die Bohrung 14 des Kolbens 3 und von dort zum Tank zurückfließen. Die zentrale Bohrung 14 des Kolbens 3 ist durch den Boden 15 vom Hydraulikraum 23 getrennt. Dadurch wirken sich die beim Verschieben des Kolbens 3 auftretenden Druckdifferenzen nicht auf das Schaltverhalten des Ventiles aus, so daß der gewünschte Kennlinienverlauf erreicht wird. Die Durchflußmenge des Hydraulikmediums ändert sich in Abhängigkeit von der Stromstärke, mit welcher der Elektromagnet 1 beaufschlagt wird, im erforderlichen Maße stetig.Since the hydraulic chamber 23 is separated from the ring channel 17 by the ring web 18 of the piston 3, the hydraulic medium displaced via the connection 8 from the unit to be driven can only flow back via this ring channel 17 and the opening 16 into the bore 14 of the piston 3 and from there to the tank. The central bore 14 of the piston 3 is separated from the hydraulic chamber 23 by the base 15. As a result, the pressure differences occurring when the piston 3 is displaced do not affect the switching behavior of the valve, so that the desired characteristic curve is achieved. The flow rate of the hydraulic medium changes depending on the current with which the electromagnet 1 is acted upon, to the extent necessary.

Claims (6)

1. Elektroproportionalmagnet-Ventileinheit mit einem Ventilgehäuse, in dem durch einen Stößel des Elektromagneten gegen Federkraft ein Kolben verschiebbar ist, der als Hohlkolben ausgebildet ist, zu dessen beiden Seiten jeweils ein Hydraulikraum liegt und der zwei Ringkanäle aufweist, die mit Arbeitsanschlüssen des Ventilgehäuses in Verbindung zu bringen sind, dadurch gekennzeichnet, daß der dem Elektromagneten (1) zugewandte Hydraulikraum (23) gegenüber dem benachbarten Ringkanal (17) und dem Hohlraum (14) des Kolbens (3) getrennt ist, und daß der Ringkanal (17) mit dem Hohlraum (14) durch wenigstens eine Öffnung (16) verbunden ist.1.Electro-proportional solenoid valve unit with a valve housing in which a plunger can be displaced by a plunger of the electromagnet against spring force, which is designed as a hollow piston, on both sides of which there is a hydraulic chamber and which has two annular channels which connect to the working connections of the valve housing are to be brought, characterized in that the hydraulic chamber (23) facing the electromagnet (1) is separated from the adjacent ring channel (17) and the cavity (14) of the piston (3), and that the ring channel (17) with the cavity (14) is connected by at least one opening (16). 2. Ventileinheit nach Anspruch 1,
dadurch gekennzeichnet, daß der Stößel (2) des Elektromagneten (1) am Boden (15) des Hohlraums (14) des Kolbens (3) anliegt.2. Valve unit according to claim 1,
characterized in that the plunger (2) of the electromagnet (1) bears against the bottom (15) of the cavity (14) of the piston (3). 3. Ventileinheit nach Anspruch 1 oder 2,
dadurch gekennzeichnet, daß die beiden Hydraulikräume (21, 23) durch mindestens eine Ausgleichsleitung (24, 25) miteinander verbunden sind.3. Valve unit according to claim 1 or 2,
characterized in that the two hydraulic spaces (21, 23) are connected to one another by at least one compensating line (24, 25). 4. Ventileinheit nach Anspruch 3,
dadurch gekennzeichnet, daß die Ausgleichsleitung (24, 25) im Kolben (3) vorgesehen ist.4. Valve unit according to claim 3,
characterized in that the compensating line (24, 25) is provided in the piston (3). 5. Ventileinheit nach Anspruch 3 oder 4,
dadurch gekennzeichnet, daß die Ausgleichsleitung (24, 25) eine axial verlaufende Bohrung im Kolben (3) ist.5. Valve unit according to claim 3 or 4,
characterized in that the compensating line (24, 25) is an axially extending bore in the piston (3). 6. Ventileinheit nach einem der Ansprüche 1 bis 5,
dadurch gekennzeichnet, daß der Kolben (3) eine stirnseitige Vertiefung (12) aufweist, in die eine Druckfeder (4) ragt.6. Valve unit according to one of claims 1 to 5,
characterized in that the piston (3) has an end-side recess (12) into which a compression spring (4) projects.
EP95100336A 1994-02-10 1995-01-12 Electro-proportional solenoid-valve unit Expired - Lifetime EP0667459B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE9402206U 1994-02-10
DE9402206U DE9402206U1 (en) 1994-02-10 1994-02-10 Electro proportional solenoid valve unit

Publications (2)

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EP0667459A1 true EP0667459A1 (en) 1995-08-16
EP0667459B1 EP0667459B1 (en) 1999-11-03

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US (1) US5592972A (en)
EP (1) EP0667459B1 (en)
JP (1) JPH07224965A (en)
DE (2) DE9402206U1 (en)

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JP3666072B2 (en) * 1995-09-13 2005-06-29 アイシン精機株式会社 Switching valve
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Also Published As

Publication number Publication date
DE9402206U1 (en) 1994-05-05
DE59507148D1 (en) 1999-12-09
JPH07224965A (en) 1995-08-22
EP0667459B1 (en) 1999-11-03
US5592972A (en) 1997-01-14

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