[go: up one dir, main page]

EP0801232A1 - A hydraulic control valve for servo controlling an aircraft, especially helicopters - Google Patents

A hydraulic control valve for servo controlling an aircraft, especially helicopters Download PDF

Info

Publication number
EP0801232A1
EP0801232A1 EP97400648A EP97400648A EP0801232A1 EP 0801232 A1 EP0801232 A1 EP 0801232A1 EP 97400648 A EP97400648 A EP 97400648A EP 97400648 A EP97400648 A EP 97400648A EP 0801232 A1 EP0801232 A1 EP 0801232A1
Authority
EP
European Patent Office
Prior art keywords
plug
annular element
rotation
balls
locking
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.)
Withdrawn
Application number
EP97400648A
Other languages
German (de)
French (fr)
Inventor
Gérard Devaud
Arnaud Libault De La Chevasnerie
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.)
Societe dApplications des Machines Motrices SAMM SA
Original Assignee
Societe dApplications des Machines Motrices SAMM SA
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 Societe dApplications des Machines Motrices SAMM SA filed Critical Societe dApplications des Machines Motrices SAMM SA
Publication of EP0801232A1 publication Critical patent/EP0801232A1/en
Withdrawn legal-status Critical Current

Links

Images

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
    • 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
    • Y10T137/8158—With indicator, register, recorder, alarm or inspection means
    • Y10T137/8225—Position or extent of motion indicator
    • Y10T137/8242—Electrical
    • 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
    • Y10T137/86638—Rotary valve
    • Y10T137/86646—Plug type

Definitions

  • the present invention relates to a hydraulic distributor intended in particular to equip servos for helicopters and airplanes.
  • French patent 2,460,435 (79 17,184, EP-A 0 021 977, US-A 4 335 745) describes a hydraulic distributor comprising a plug mounted rotatably in a fixed fur housed in a body with the interposition of an annular element between bushel and fur. Bores are provided radially in the fur and in the annular element in the extension of each other, for the entry under pressure and the outlet to the tank of a hydraulic fluid. Passages are provided on the periphery of the annular element to allow the circulation of the fluid from one bore to the other in the event of jamming of the plug in said annular element. Means are provided for locking in rotation, in normal service, the annular element and for allowing the drive of said element in rotation by the plug in the event of jamming of the latter in the annular element.
  • this dispenser has all the desired operational safety.
  • the device for holding the fixed annular element during normal operation of the dispenser and for releasing it in rotation in the event of jamming of the plug comprises, in this anterior dispenser, balls partially engaged in notches formed on one end of the annular element, and which are kept applied in these notches, by means of a plate, by a balance articulated on the body.
  • the end of this balance opposite to the balls is urged by a push device arranged laterally to the body of the distributor and parallel to the plug, this push being permanently urged by a spring so as to exert on the balance a holding torque of the balls in their notches.
  • the pusher cooperates with an electric contactor connected to an alarm lamp, which can be lit when the balls push the balance against the action of the return spring following a rotation of the annular element, in the event of seizure bushel in the latter.
  • Such a locking device is relatively bulky considering the space available at the location of the distributor, in a helicopter or an airplane.
  • the means for locking the annular element in rotation in normal service comprises a push device mounted laterally on the body at one end of the plug and directed perpendicularly to the latter, and this device is provided with elastic means. urging the pusher against a rocker inside the body and the thrust of which applies to locking balls projecting from notches formed in one end of the annular element.
  • Such a device is significantly less bulky than the device of the aforementioned French patent.
  • the invention also aims to provide a distributor equipped with a system for detecting the angular position of the rotary plug, which is compact.
  • the distributor is equipped with at least one inductive detector of the angular position of the rotary plug, comprising a movable core, one end of which is articulated on an arm extending radially to the plug and integral with the latter in rotation, the core being housed in induction windings.
  • the distributor is equipped with two linear inductive sensors, coupled to one another and arranged on either side of the push-button locking system, so that when one of the two cores enters the 'corresponding winding, the second core leaves the associated winding.
  • Figure 1 is an axial sectional view of an embodiment of the hydraulic distributor according to the invention.
  • Figure 2 is a simplified top view of the dispenser of Figure 1 showing the locking device in rotation of the annular element and two inductive sensors of the angular position of the plug, placed on each side of the locking device.
  • FIG. 3 is a side elevation view along the arrow K in FIG. 1.
  • FIG. 4 is a half-sectional mid-elevation view on an enlarged scale with respect to FIG. 3, of an inductive detector of the angular position of the plug.
  • FIG. 5 is a sectional view of the distributor along 5-5 of FIG. 1.
  • the hydraulic distributor shown in the drawings is intended to be part of a hydraulic servo-control device, usable in particular on airplanes or helicopters, of the type described in French patent 2,460,435, the description of which will therefore not be repeated here. .
  • the dispenser comprises a central plug 1 arranged for its greater part inside a body 2 and one end of which protrudes 3 and is adapted to be secured with a control lever as described in the aforementioned French patent.
  • the plug 1 is disposed axially in an annular element forming a liner 4 itself housed coaxially in a concentric sleeve 5 fixed to the body 2 by means of an annular part 6.
  • the fur 5 and the annular part 6 are pierced with two pairs of bores 7, 8 respectively arranged radially and distributed over the periphery of these parts.
  • radial bores 9 are also formed in the annular element 4.
  • bores 7, 8, 9 are part of a hydraulic circuit allowing the entry under pressure and the outlet to the tank of a hydraulic fluid, passages being provided on the periphery of the annular element 4 to allow the circulation of the fluid from one bore to the other in the event of seizure of the plug 1 in the jacket 4.
  • the entire hydraulic circuit of this distributor is described in detail in French patent 2,460,435.
  • the annular element 4 and the plug 1 are mounted, at one of their ends, on ball bearings 11 placed in abutment on shoulders inside the body 2.
  • the means for locking in rotation of the annular element 4, in normal service of the dispenser, comprise a device 12 with pusher 13 mounted laterally on the body 2, at one end of the plug 1, the pusher 13 being directed perpendicularly to the latter.
  • the device 12 comprises a housing 14 containing a helical spring 15 bearing on an annular shoulder 16 of the housing 14 and the opposite end of which exerts an axial thrust on a bell 17 integral with a rod constituting the axial pusher 13.
  • the housing 14 is partially engaged in a corresponding recess in body 2.
  • the end of the pusher 13 requests a rocker lever 30 inside the body, articulated on an axis 18 mounted on the body 2 transversely to the pusher 13.
  • the rocker 30 has two legs 30a forming a fork which surrounds the end of the plug 1.
  • the lugs 30a thus exert on a washer 19 coaxial with the plug 1 a push having an axial component on the plug 1.
  • This push is applied on several balls 21 distributed around the periphery of the end of the annular element 4.
  • An eccentric 45 is mounted on the body 2 substantially at the level of the balls 21 and transversely to the plug 1. This eccentric 45 is used, in a manner known per se, for adjusting the hydraulic zero of the plug 1 via the liner 4.
  • the balls 21, preferably arranged at equal angular intervals around the plug 1, are engaged in corresponding diametric openings 22 arranged in a plate 23 inside the body 2, extending perpendicular to the plug 1, which passes through it through a corresponding central opening .
  • the balls 21 are also partially pressed into notches 24, preferably with a V-shaped profile, formed in the end face of the jacket 4.
  • the locking device which has just been described is notably less bulky than that of the aforementioned French patent, thanks to its arrangement lateral to the plug 1.
  • the bell 17 has its translational travel limited by the bottom 10 of the housing 14 fitted into the body 2.
  • the distributor is also equipped with at least one inductive detector 25 for the angular position of the rotary plug 1, which makes it possible to control the position of the latter.
  • the distributor thus comprises two detectors 25, arranged on either side of the locking device 12 of the rotating sleeve 4 (FIG. 2), these two detectors 25 being coupled one to the other. 'other.
  • Each detector 25 is of the linear type, comprising inductive windings 26, the outlet 46 of which can be seen (FIG. 4), arranged in a housing 27 suitably fixed on the body 2 and provided with an axial core 28, displaceable in translation axial inside the windings 26.
  • Each core 28 is constituted by a tube of which a part 28 has protruded outside the housing 27, the end of this part 28 a being articulated by an axis 29 on an arm 31 extending radially to the plug 1 and integral in rotation with one end of the latter.
  • the two arms 31 are thus secured to the plug 1 and form an appropriate angle between them, defining a widely open V.
  • Each core 28 passes through the end of the corresponding housing 27 through an opening 32 substantially greater than the outside diameter of the core 28. This arrangement reserves for the latter a possibility of clearance. transverse in the housing 27, due to the rotations of its articulation on the associated arm 31 linked to the plug 1.
  • the hydraulic distributor targeted by the invention comprises a device for testing the proper functioning of the locking means 12 of the jacket 4.
  • This test device 33 (visible in FIG. 5) comprises a jack 34 housed in the body 2.
  • the cylinder 34 comprises a cylinder 35 containing a piston 36 provided with a rod 37 perpendicular to the axis of the plug 1, and which is constantly stressed by a helical spring 38 inside the cylinder 35.
  • the rod 37 is thus constantly applied against a lug radial 39 projecting from a collar 41 mounted at the end of the annular element 4 where the locking balls 21 are mounted, and secured in rotation with the jacket 4 by a radial pin 42.
  • the jack 34 is positioned in a cylindrical chamber 43 communicating with the hydraulic supply circuit.
  • this test cylinder device 34 makes it possible to verify that the locking device 12 of the jacket 4 in its normal position allows the rotation of this jacket when a sufficient torque is exerted on it, in the absence of pressurization of the hydraulic chamber 43.
  • the size of the cylinder test device 34 of the distributor according to the invention is much smaller than that of the distributor of the aforementioned patent.

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Mechanical Engineering (AREA)
  • General Engineering & Computer Science (AREA)
  • Indication Of The Valve Opening Or Closing Status (AREA)
  • Fluid-Pressure Circuits (AREA)
  • Actuator (AREA)

Abstract

The distributor incorporates a cock (1) rotatable within a ring (4) fitted into a fixed ferrule (5) in the body (2). In normal use the ring is locked so that it can be driven by the cock. The laterally mounted locking device (12) includes a plunger (13) directed perpendicularly at one end of the cock. A helical spring (15) urges the plunger against a rocker (30) within the body which exerts pressure on locking balls (21) protruding from sockets (24) in one end of the ring.

Description

La présente invention a pour objet un distributeur hydraulique destiné notamment à équiper des servocommandes d'hélicoptères et d'avions.The present invention relates to a hydraulic distributor intended in particular to equip servos for helicopters and airplanes.

Le brevet français 2 460 435 (79 17 184, EP-A 0 021 977, US-A 4 335 745) décrit un distributeur hydraulique comprenant un boisseau monté rotativement dans une fourrure fixe logée dans un corps avec interposition d'un élément annulaire entre le boisseau et la fourrure. Des alésages sont ménagés radialement dans la fourrure et dans l'élément annulaire dans le prolongement les uns des autres, pour l'entrée sous pression et la sortie à la bâche d'un fluide hydraulique. Des passages sont prévus sur la périphérie de l'élément annulaire pour permettre la circulation du fluide d'un alésage à l'autre en cas de grippage du boisseau dans ledit élément annulaire. Des moyens sont prévus pour verrouiller en rotation, en service normal, l'élément annulaire et pour permettre l'entraînement dudit élément en rotation par le boisseau en cas de grippage de ce dernier dans l'élément annulaire.French patent 2,460,435 (79 17,184, EP-A 0 021 977, US-A 4 335 745) describes a hydraulic distributor comprising a plug mounted rotatably in a fixed fur housed in a body with the interposition of an annular element between bushel and fur. Bores are provided radially in the fur and in the annular element in the extension of each other, for the entry under pressure and the outlet to the tank of a hydraulic fluid. Passages are provided on the periphery of the annular element to allow the circulation of the fluid from one bore to the other in the event of jamming of the plug in said annular element. Means are provided for locking in rotation, in normal service, the annular element and for allowing the drive of said element in rotation by the plug in the event of jamming of the latter in the annular element.

Ainsi, au cas où par suite d'un grippage anormal du boisseau dans l'élément annulaire, ou d'un blocage du boisseau dans cet élément dû à l'insertion accidentelle d'un corps étranger, le couple nécessaire pour faire tourner le boisseau dans l'élément annulaire devient trop important, ce dernier est entraîné en rotation, de sorte que la circulation du fluide hydraulique dans le distributeur reste assurée. En effet les moyens de verrouillage précités sont automatiquement débloqués lorsqu'un couple suffisant est exercé sur l'élément annulaire.Thus, in the event that as a result of abnormal seizure of the plug in the annular element, or a blockage of the plug in this element due to the accidental insertion of a foreign body, the torque necessary to rotate the plug in the annular element becomes too large, the latter is rotated, so that the circulation of the hydraulic fluid in the distributor remains ensured. Indeed, the aforementioned locking means are automatically released when a sufficient torque is exerted on the annular element.

Ainsi, ce distributeur présente toute la sécurité de fonctionnement voulue.Thus, this dispenser has all the desired operational safety.

Le dispositif de maintien de l'élément annulaire fixe pendant le fonctionnement normal du distributeur et pour le libérer en rotation en cas de grippage du boisseau, comprend, dans ce distributeur antérieur, des billes engagées partiellement dans des encoches formées sur une extrémité de l'élément annulaire, et qui sont maintenues appliquées dans ces encoches, par l'intermédiaire d'un plateau, par un balancier articulé sur le corps. L'extrémité de ce balancier opposée aux billes est sollicitée par un dispositif à poussoir disposé latéralement au corps du distributeur et parallèlement au boisseau, ce poussoir étant sollicité en permanence par un ressort de façon à exercer sur le balancier un couple de maintien en place des billes dans leurs encoches. Le poussoir coopère avec un contacteur électrique connecté à une lampe d'alarme, qui peut être allumée lorsque les billes repoussent le balancier contre l'action du ressort de rappel à la suite d'une rotation de l'élément annulaire, en cas de grippage du boisseau dans ce dernier.The device for holding the fixed annular element during normal operation of the dispenser and for releasing it in rotation in the event of jamming of the plug, comprises, in this anterior dispenser, balls partially engaged in notches formed on one end of the annular element, and which are kept applied in these notches, by means of a plate, by a balance articulated on the body. The end of this balance opposite to the balls is urged by a push device arranged laterally to the body of the distributor and parallel to the plug, this push being permanently urged by a spring so as to exert on the balance a holding torque of the balls in their notches. The pusher cooperates with an electric contactor connected to an alarm lamp, which can be lit when the balls push the balance against the action of the return spring following a rotation of the annular element, in the event of seizure bushel in the latter.

Un tel dispositif de verrouillage est relativement encombrant compte tenu de l'espace disponible à l'emplacement du distributeur, dans un hélicoptère ou un avion.Such a locking device is relatively bulky considering the space available at the location of the distributor, in a helicopter or an airplane.

Conformément à l'invention, les moyens de verrouillage de l'élément annulaire en rotation en service normal comprennent un dispositif à poussoir monté latéralement sur le corps à une extrémité du boisseau et dirigé perpendiculairement à ce dernier, et ce dispositif est pourvu de moyens élastiques sollicitant le poussoir contre un basculeur intérieur au corps et dont la poussée s'applique sur des billes de verrouillage faisant saillie d'encoches ménagées dans une extrémité de l'élément annulaire.According to the invention, the means for locking the annular element in rotation in normal service comprises a push device mounted laterally on the body at one end of the plug and directed perpendicularly to the latter, and this device is provided with elastic means. urging the pusher against a rocker inside the body and the thrust of which applies to locking balls projecting from notches formed in one end of the annular element.

Un tel dispositif est sensiblement moins encombrant que le dispositif du brevet français précité.Such a device is significantly less bulky than the device of the aforementioned French patent.

L'invention a également pour but de réaliser un distributeur équipé d'un système détecteur de la position angulaire du boisseau rotatif, qui soit peu encombrant.The invention also aims to provide a distributor equipped with a system for detecting the angular position of the rotary plug, which is compact.

Suivant une caractéristique complémentaire de l'invention, le distributeur est équipé d'au moins un détecteur inductif de la position angulaire du boisseau rotatif, comprenant un noyau mobile dont une extrémité est articulée sur un bras s'étendant radialement au boisseau et solidaire de ce dernier en rotation, le noyau étant logé dans des enroulements d'induction.According to a complementary characteristic of the invention, the distributor is equipped with at least one inductive detector of the angular position of the rotary plug, comprising a movable core, one end of which is articulated on an arm extending radially to the plug and integral with the latter in rotation, the core being housed in induction windings.

De préférence, le distributeur est équipé de deux détecteurs inductifs linéaires, couplés l'un à l'autre et disposés de part et d'autre du système de verrouillage à poussoir, de telle sorte que lorsque l'un des deux noyaux pénètre dans l'enroulement correspondant, le second noyau sort de l'enroulement associé.Preferably, the distributor is equipped with two linear inductive sensors, coupled to one another and arranged on either side of the push-button locking system, so that when one of the two cores enters the 'corresponding winding, the second core leaves the associated winding.

D'autres particularités et avantages de l'invention apparaîtront au cours de la description qui va suivre, faite en référence aux dessins annexés qui en illustrent une forme de réalisation à titre d'exemple non limitatif.Other features and advantages of the invention will become apparent during the description which follows, given with reference to the appended drawings which illustrate an embodiment thereof by way of nonlimiting example.

La figure 1 est une vue en coupe axiale d'une forme de réalisation du distributeur hydraulique selon l'invention.Figure 1 is an axial sectional view of an embodiment of the hydraulic distributor according to the invention.

La figure 2 est une vue de dessus simplifiée du distributeur de la figure 1, montrant le dispositif de verrouillage en rotation de l'élément annulaire ainsi que deux détecteurs inductifs de la position angulaire du boisseau, placés de chaque côté du dispositif de verrouillage.Figure 2 is a simplified top view of the dispenser of Figure 1 showing the locking device in rotation of the annular element and two inductive sensors of the angular position of the plug, placed on each side of the locking device.

La figure 3 est une vue en élévation latérale suivant la flèche K de la figure 1.FIG. 3 is a side elevation view along the arrow K in FIG. 1.

La figure 4 est une vue mi-coupe mi-élévation à échelle agrandie par rapport à la figure 3, d'un détecteur inductif de la position angulaire du boisseau.FIG. 4 is a half-sectional mid-elevation view on an enlarged scale with respect to FIG. 3, of an inductive detector of the angular position of the plug.

La figure 5 est une vue en coupe du distributeur suivant 5-5 de la figure 1.FIG. 5 is a sectional view of the distributor along 5-5 of FIG. 1.

Le distributeur hydraulique représenté aux dessins est destiné à faire partie d'un dispositif de servocommandes hydrauliques, utilisable notamment sur des avions ou des hélicoptères, du type de celui décrit dans le brevet français 2 460 435, dont la description ne sera donc pas reprise ici.The hydraulic distributor shown in the drawings is intended to be part of a hydraulic servo-control device, usable in particular on airplanes or helicopters, of the type described in French patent 2,460,435, the description of which will therefore not be repeated here. .

Le distributeur comprend un boisseau central 1 disposé pour sa plus grande partie à l'intérieur d'un corps 2 et dont une extrémité 3 fait saillie et est adaptée pour être solidarisée avec un levier de commande tel que décrit dans le brevet français précité.The dispenser comprises a central plug 1 arranged for its greater part inside a body 2 and one end of which protrudes 3 and is adapted to be secured with a control lever as described in the aforementioned French patent.

Le boisseau 1 est disposé axialement dans un élément annulaire formant un chemisage 4 lui-même logé coaxialement dans une fourrure concentrique 5 fixée au corps 2 par l'intermédiaire d'une pièce annulaire 6.The plug 1 is disposed axially in an annular element forming a liner 4 itself housed coaxially in a concentric sleeve 5 fixed to the body 2 by means of an annular part 6.

La fourrure 5 et la pièce annulaire 6 sont percées de deux couples d'alésages 7, 8 respectivement ménagés radialement et répartis sur la périphérie de ces pièces. Dans le prolongement des alésages 7, 8, sont également formés, dans l'élément annulaire 4, des alésages radiaux 9.The fur 5 and the annular part 6 are pierced with two pairs of bores 7, 8 respectively arranged radially and distributed over the periphery of these parts. In the extension of the bores 7, 8, radial bores 9 are also formed in the annular element 4.

Ces alésages 7, 8, 9 font partie d'un circuit hydraulique permettant l'entrée sous pression et la sortie à la bâche d'un fluide hydraulique, des passages étant prévus sur la périphérie de l'élément annulaire 4 pour permettre la circulation du fluide d'un alésage à l'autre en cas de grippage du boisseau 1 dans la chemise 4. L'ensemble du circuit hydraulique de ce distributeur est décrit en détail dans le brevet français 2 460 435.These bores 7, 8, 9 are part of a hydraulic circuit allowing the entry under pressure and the outlet to the tank of a hydraulic fluid, passages being provided on the periphery of the annular element 4 to allow the circulation of the fluid from one bore to the other in the event of seizure of the plug 1 in the jacket 4. The entire hydraulic circuit of this distributor is described in detail in French patent 2,460,435.

L'élément annulaire 4 et le boisseau 1 sont montés, à l'une de leurs extrémités, sur des roulements à billes 11 placés en appui sur des épaulements intérieurs au corps 2.The annular element 4 and the plug 1 are mounted, at one of their ends, on ball bearings 11 placed in abutment on shoulders inside the body 2.

Les moyens de verrouillage en rotation de l'élément annulaire 4, en service normal du distributeur, comprennent un dispositif 12 à poussoir 13 monté latéralement sur le corps 2, à une extrémité du boisseau 1, le poussoir 13 étant dirigé perpendiculairement à ce dernier. Le dispositif 12 comprend un boîtier 14 contenant un ressort hélicoïdal 15 prenant appui sur un épaule' ment annulaire 16 du boîtier 14 et dont l'extrémité opposée exerce une poussée axiale sur une cloche 17 solidaire d'une tige constituant le poussoir axial 13. Le boîtier 14 est partiellement engagé dans un évidement correspondant du corps 2.The means for locking in rotation of the annular element 4, in normal service of the dispenser, comprise a device 12 with pusher 13 mounted laterally on the body 2, at one end of the plug 1, the pusher 13 being directed perpendicularly to the latter. The device 12 comprises a housing 14 containing a helical spring 15 bearing on an annular shoulder 16 of the housing 14 and the opposite end of which exerts an axial thrust on a bell 17 integral with a rod constituting the axial pusher 13. The housing 14 is partially engaged in a corresponding recess in body 2.

L'extrémité du poussoir 13 sollicite un levier basculeur 30 intérieur au corps, articulé sur un axe 18 monté sur le corps 2 transversalement au poussoir 13. le basculeur 30 comporte deux pattes 30a formant une fourche qui entoure l'extrémité du boisseau 1. Les pattes 30a exercent ainsi sur une rondelle 19 coaxiale au boisseau 1 une poussée ayant une composante axiale au boisseau 1. Cette poussée s'applique sur plusieurs billes 21 réparties sur le pourtour de l'extrémité de l'élément annulaire 4.The end of the pusher 13 requests a rocker lever 30 inside the body, articulated on an axis 18 mounted on the body 2 transversely to the pusher 13. the rocker 30 has two legs 30a forming a fork which surrounds the end of the plug 1. The lugs 30a thus exert on a washer 19 coaxial with the plug 1 a push having an axial component on the plug 1. This push is applied on several balls 21 distributed around the periphery of the end of the annular element 4.

Un excentrique 45 est monté sur le corps 2 sensiblement au niveau des billes 21 et transversalement au boisseau 1. Cet excentrique 45 sert, de façon connue en soi, au réglage du zéro hydraulique du boisseau 1 via le chemisage 4.An eccentric 45 is mounted on the body 2 substantially at the level of the balls 21 and transversely to the plug 1. This eccentric 45 is used, in a manner known per se, for adjusting the hydraulic zero of the plug 1 via the liner 4.

Les billes 21, de préférence disposées à intervalles angulaires égaux autour du boisseau 1, sont engagées dans des ouvertures diamétrales correspondantes 22 agencées dans un plateau 23 intérieur au corps 2, s'étendant perpendiculairement au boisseau 1, qui le traverse par une ouverture centrale correspondante. Les billes 21 sont de plus partiellement enfoncées dans des encoches 24, à profil de préférence en V, ménagées dans la face terminale de la chemise 4.The balls 21, preferably arranged at equal angular intervals around the plug 1, are engaged in corresponding diametric openings 22 arranged in a plate 23 inside the body 2, extending perpendicular to the plug 1, which passes through it through a corresponding central opening . The balls 21 are also partially pressed into notches 24, preferably with a V-shaped profile, formed in the end face of the jacket 4.

De ce fait, en service normal du distributeur, lorsqu'il ne se produit aucun grippage entre le boisseau 1 et la chemise 4, donc lorsque le boisseau 1 tourne normalement autour de son axe par rapport à la chemise 4, celle-ci est maintenue immobile en rotation par la poussée du ressort 15 sur les billes de verrouillage 21, par l'intermédiaire du poussoir 13, du basculeur 30 et de la rondelle 19.Therefore, in normal service of the dispenser, when there is no seizure between the plug 1 and the jacket 4, so when the valve 1 normally rotates about its axis relative to the jacket 4, the latter is maintained stationary in rotation by the thrust of the spring 15 on the locking balls 21, by means of the pusher 13, the rocker 30 and the washer 19.

Lorsqu'une cause accidentelle entraîne un grippage du boisseau 1 par rapport à la chemise 4, celle-ci est entraînée en rotation par le boisseau 1 dés que le couple développé par le boisseau est supérieur au couple antagoniste de maintien des billes 21 dans les encoches 24, développé par le ressort 15, le poussoir 13 et le basculeur 30. Dans ce cas, le couple de grippage du boisseau 1 entraîne en rotation la chemise 4, ce qui fait sortir les billes 21 de leurs encoches 24, et soulève la rondelle 19 à l'encontre de la force de rappel antagoniste du poussoir 13 et du ressort 15.When an accidental cause causes seizure of the plug 1 with respect to the jacket 4, the latter is rotated by the plug 1 as soon as the torque developed by the plug is greater than the opposing torque for holding the balls 21 in the notches 24, developed by the spring 15, the plunger 13 and the rocker 30. In this case, the gripping torque of the plug 1 rotates the jacket 4, which causes the balls 21 to come out of their notches 24, and lifts the washer 19 to the against the opposing restoring force of the plunger 13 and the spring 15.

Le dispositif de verrouillage qui vient d'être décrit est notablement moins encombrant que celui du brevet français précité, grâce à son agencement latéral au boisseau 1.The locking device which has just been described is notably less bulky than that of the aforementioned French patent, thanks to its arrangement lateral to the plug 1.

La cloche 17 a sa course en translation limitée par le fond 10 du boîtier 14 emboîté dans le corps 2.The bell 17 has its translational travel limited by the bottom 10 of the housing 14 fitted into the body 2.

Le distributeur est également équipé d'au moins un détecteur inductif 25 de la position angulaire du boisseau rotatif 1, qui permet de réaliser un asservissement de la position de celui-ci. Dans l'exemple de réalisation décrit, le distributeur comporte ainsi deux détecteurs 25, disposés de part et d'autre du dispositif de verrouillage 12 de la chemise 4 en rotation (figure 2), ces deux détecteurs 25 étant couplés l'un à l'autre.The distributor is also equipped with at least one inductive detector 25 for the angular position of the rotary plug 1, which makes it possible to control the position of the latter. In the embodiment described, the distributor thus comprises two detectors 25, arranged on either side of the locking device 12 of the rotating sleeve 4 (FIG. 2), these two detectors 25 being coupled one to the other. 'other.

Chaque détecteur 25 est du type linéaire, comprenant des enroulements inductifs 26, dont on voit la sortie 46 (figure 4), disposés dans un boîtier 27 fixé de manière appropriée sur le corps 2 et pourvu d'un noyau axial 28, déplaçable en translation axiale à l'intérieur des enroulements 26. Chaque noyau 28 est constitué par un tube dont une partie 28a fait saillie à l'extérieur du boîtier 27, l'extrémité de cette partie 28a étant articulée par un axe 29 sur un bras 31 s'étendant radialement au boisseau 1 et solidaire en rotation d'une extrémité de ce dernier. Les deux bras 31 sont ainsi solidarisés avec le boisseau 1 et forment entre eux un angle approprié, en définissant un V largement ouvert.Each detector 25 is of the linear type, comprising inductive windings 26, the outlet 46 of which can be seen (FIG. 4), arranged in a housing 27 suitably fixed on the body 2 and provided with an axial core 28, displaceable in translation axial inside the windings 26. Each core 28 is constituted by a tube of which a part 28 has protruded outside the housing 27, the end of this part 28 a being articulated by an axis 29 on an arm 31 extending radially to the plug 1 and integral in rotation with one end of the latter. The two arms 31 are thus secured to the plug 1 and form an appropriate angle between them, defining a widely open V.

Chaque noyau 28 traverse l'extrémité du boîtier correspondant 27 par une ouverture 32 sensiblement supérieure au diamètre extérieur du noyau 28. Cet agencement réserve pour ce dernier une possibilité de débattement transversal dans le boîtier 27, à raison des rotations de son articulation sur le bras associé 31 lié au boisseau 1.Each core 28 passes through the end of the corresponding housing 27 through an opening 32 substantially greater than the outside diameter of the core 28. This arrangement reserves for the latter a possibility of clearance. transverse in the housing 27, due to the rotations of its articulation on the associated arm 31 linked to the plug 1.

Le distributeur hydraulique visé par l'invention comprend un dispositif de test du bon fonctionnement des moyens de verrouillage 12 de la chemise 4. Ce dispositif de test 33 (visible à la figure 5), comprend un vérin 34 logé dans le corps 2. Le vérin 34 comprend un cylindre 35 contenant un piston 36 pourvu d'une tige 37 perpendiculaire à l'axe du boisseau 1, et qui est constamment sollicitée par un ressort hélicoïdal 38 intérieur au cylindre 35. La tige 37 est ainsi constamment appliquée contre une patte radiale 39 faisant saillie d'un collier 41 monté à l'extrémité de l'élément annulaire 4 où sont montées les billes de verrouillage 21, et solidarisé en rotation avec la chemise 4 par un pion radial 42. D'autre part le vérin 34 est positionné dans une chambre cylindrique 43 communiquant avec le circuit hydraulique d'alimentation.The hydraulic distributor targeted by the invention comprises a device for testing the proper functioning of the locking means 12 of the jacket 4. This test device 33 (visible in FIG. 5) comprises a jack 34 housed in the body 2. The cylinder 34 comprises a cylinder 35 containing a piston 36 provided with a rod 37 perpendicular to the axis of the plug 1, and which is constantly stressed by a helical spring 38 inside the cylinder 35. The rod 37 is thus constantly applied against a lug radial 39 projecting from a collar 41 mounted at the end of the annular element 4 where the locking balls 21 are mounted, and secured in rotation with the jacket 4 by a radial pin 42. On the other hand the jack 34 is positioned in a cylindrical chamber 43 communicating with the hydraulic supply circuit.

Ce dispositif de test fonctionne de la même manière que celui décrit dans le brevet français 2 460 435 (EP-A-0021 977), de sorte que ce fonctionnement ne sera pas repris ici en détail.This test device operates in the same way as that described in French patent 2,460,435 (EP-A-0021 977), so that this operation will not be repeated here in detail.

On indiquera seulement que si la chambre 43 n'est pas sous pression par suite de l'absence d'huile provenant du circuit hydraulique, la poussée du ressort 38 sur le piston 36 s'exerce sans contrepartie, de sorte que le piston 36 vient en butée au fond du cylindre 35 et la tige 37 entraîne en rotation, dans le sens horaire, le bras 39 et la chemise 4.It will only be indicated that if the chamber 43 is not under pressure owing to the absence of oil from the hydraulic circuit, the thrust of the spring 38 on the piston 36 is exerted without compensation, so that the piston 36 comes in abutment at the bottom of the cylinder 35 and the rod 37 rotates, clockwise, the arm 39 and the jacket 4.

De ce fait les billes 21 sont poussées vers l'extérieur de leurs encoches 24, glissent sur les rampes inclinées de celles-ci, coulissent dans les ouvertures de passage du plateau-guide 23, et font pivoter le basculeur 30 autour de l'axe 18. Le poussoir 13 recule et, par l'intermédiaire de la cloche 17, déclenche un contacteur switch 20 intérieur au boîtier 14. Ce switch 20 allume à son tour la lampe d'alarme (non représentée), laquelle indique par conséquent à l'opérateur que l'élément annulaire 4 est déverrouillé de sa position normale. L'introduction du fluide hydraulique sous pression dans la chambre 43 jusqu'à ce que sa pression devienne prépondérante par rapport à la sollicitation antagoniste du ressort 38 ramène le vérin 34, le bras 39 et la chemise 4 à leurs positions initiales.As a result, the balls 21 are pushed towards the outside of their notches 24, slide on the inclined ramps of the latter, slide in the openings of passage of the guide plate 23, and rotate the rocker 30 around the axis. 18. The push-button 13 moves back and, by means of the bell 17, triggers a switch 20 inside the housing 14. This switch 20 in turn turns on the alarm lamp (not shown), which therefore indicates to the operator that the annular element 4 is unlocked from its normal position. The introduction of the hydraulic fluid under pressure into the chamber 43 until its pressure becomes preponderant with respect to the opposing stress of the spring 38 brings the jack 34, the arm 39 and the jacket 4 back to their initial positions.

Ainsi ce dispositif à vérin de test 34 permet de vérifier que le dispositif de verrouillage 12 de la chemise 4 dans sa position normale autorise la rotation de cette chemise lorsqu'un couple suffisant est exercé sur celle-ci, en l'absence de pressurisation de la chambre hydraulique 43.Thus, this test cylinder device 34 makes it possible to verify that the locking device 12 of the jacket 4 in its normal position allows the rotation of this jacket when a sufficient torque is exerted on it, in the absence of pressurization of the hydraulic chamber 43.

Comme on peut s'en rendre compte en comparant la figure 5 annexée à la figure 5 du brevet français précité, l'encombrement du dispositif de test à vérin 34 du distributeur selon l'invention est largement inférieur à celui du distributeur du brevet précité.As can be seen by comparing FIG. 5 appended to FIG. 5 of the aforementioned French patent, the size of the cylinder test device 34 of the distributor according to the invention is much smaller than that of the distributor of the aforementioned patent.

Claims (6)

Distributeur hydraulique destiné notamment à équiper des servocommandes d'hélicoptères et d'avions, comprenant un boisseau (1) monté rotativement dans une fourrure (5) fixe logée dans un corps (2) avec interposition d'un élément annulaire (4) entre le boisseau et la fourrure, des alésages (7, 8) étant ménagés radialement dans ladite fourrure et dans l'élément annulaire dans le prolongement les uns des autres pour l'entrée sous pression et la sortie à la bâche d'un fluide hydraulique, des passages étant prévus sur la périphérie de l'élément annulaire (4) pour permettre la circulation du fluide d'un alésage à l'autre en cas de grippage du boisseau dans ledit élément annulaire, et des moyens sont prévus pour verrouiller en rotation en service normal l'élément annulaire et pour permettre l'entraînement du dit élément en rotation par le boisseau en cas de grippage de ce dernier dans l'élément annulaire, caractérisé en ce que les moyens de verrouillage de l'élément annulaire en rotation en service normal comprennent un dispositif (12) à poussoir (13) monté latéralement sur le corps à une extrémité du boisseau (1) et dirigé perpendiculairement à ce dernier, pourvu de moyens élastiques (15) sollicitant ce poussoir contre un basculeur (30) intérieur au corps et dont la poussée s'applique sur des billes (21) de verrouillage faisant saillie d'encoches (24) ménagées dans une extrémité de l'élément annulaire.Hydraulic distributor intended in particular to equip servos for helicopters and airplanes, comprising a plug (1) rotatably mounted in a fixed fur (5) housed in a body (2) with the interposition of an annular element (4) between the bushel and the fur, bores (7, 8) being formed radially in said fur and in the annular element in the extension of each other for the entry under pressure and the exit to the tank of a hydraulic fluid, passages being provided on the periphery of the annular element (4) to allow the circulation of the fluid from one bore to the other in the event of jamming of the plug in said annular element, and means are provided for locking in rotation in service normal the annular element and to allow the drive of said element in rotation by the plug in the event of seizure of the latter in the annular element, characterized in that the locking means d e the annular element in rotation in normal service comprises a device (12) with pusher (13) mounted laterally on the body at one end of the plug (1) and directed perpendicularly to the latter, provided with elastic means (15) urging this pusher against a rocker (30) inside the body and the thrust of which applies to locking balls (21) projecting from notches (24) formed in one end of the annular element. Distributeur selon la revendication 1, caractérisé en ce qu'il comporte une rondelle (19) interposée entre le poussoir (13) et les billes (21), traversée axialement par l'extrémité du boisseau (1) et maintenue appliquée sur les billes par le poussoir, ces billes étant réparties sur le pourtour de l'extrémité de l'élément annulaire (4).Distributor according to claim 1, characterized in that it comprises a washer (19) interposed between the pusher (13) and the balls (21), traversed axially by the end of the plug (1) and kept applied to the balls by the pusher, these balls being distributed around the periphery of the end of the annular element (4). Distributeur selon la revendication 2, caractérisé en ce que le basculeur (30) est articulé sur un axe (18) monté sur le corps (2) et comporte deux pattes (30a) entourant le boisseau (1) et maintenues appliquées sur la rondelle (19).Distributor according to claim 2, characterized in that the rocker (30) is articulated on an axis (18) mounted on the body (2) and comprises two tabs (30 a ) surrounding the plug (1) and kept applied to the washer (19). Distributeur selon l'une des revendications 1 à 3, caractérisé en ce qu'il est équipé d'au moins un détecteur inductif (25) de la position angulaire du boisseau rotatif (1), comprenant un noyau mobile (28) dont une extrémité (28a) est articulée sur un bras (31) s'étendant radialement au boisseau et solidaire de ce dernier en rotation, le noyau étant logé dans des enroulements d'induction (26).Distributor according to one of claims 1 to 3, characterized in that it is equipped with at least one inductive detector (25) of the angular position of the rotary plug (1), comprising a movable core (28), one end of which (28a) is articulated on an arm (31) extending radially to the plug and integral with the latter in rotation, the core being housed in induction windings (26). Distributeur selon la revendication 4, caractérisé en ce que le noyau (28) fait saillie d'un boîtier (27) contenant les enroulements (26), avec possibilité de débattement transversal dans une ouverture (32) du boîtier (27) à raison des rotations de son articulation sur le bras (31) lié au boisseau (1).Distributor according to claim 4, characterized in that the core (28) projects from a housing (27) containing the windings (26), with the possibility of transverse movement in an opening (32) of the housing (27) due to the rotations of its articulation on the arm (31) linked to the plug (1). Distributeur selon la revendication 4, caractérisé en ce qu'il comprend un dispositif de test de verrouillage de l'élément annulaire (4), ce dispositif comprenant un vérin hydraulique (34) monté dans le corps (2), équipé d'un piston (36) poussé par un organe élastique (38) et dont la tige (39) sollicite un bras radial (39) solidaire en rotation dudit élément (4).Distributor according to claim 4, characterized in that it comprises a device for testing the locking of the annular element (4), this device comprising a hydraulic cylinder (34) mounted in the body (2), equipped with a piston (36) pushed by an elastic member (38) and whose rod (39) urges a radial arm (39) integral in rotation with said element (4).
EP97400648A 1996-04-03 1997-03-21 A hydraulic control valve for servo controlling an aircraft, especially helicopters Withdrawn EP0801232A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9604197A FR2747174B1 (en) 1996-04-03 1996-04-03 HYDRAULIC DISTRIBUTOR FOR AIRCRAFT SERVO CONTROLS, ESPECIALLY HELICOPTERS
FR9604197 1996-04-03

Publications (1)

Publication Number Publication Date
EP0801232A1 true EP0801232A1 (en) 1997-10-15

Family

ID=9490878

Family Applications (1)

Application Number Title Priority Date Filing Date
EP97400648A Withdrawn EP0801232A1 (en) 1996-04-03 1997-03-21 A hydraulic control valve for servo controlling an aircraft, especially helicopters

Country Status (3)

Country Link
US (1) US5899226A (en)
EP (1) EP0801232A1 (en)
FR (1) FR2747174B1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19926429A1 (en) * 1999-06-10 2000-12-14 Zf Luftfahrttechnik Gmbh Device for locking several actuators at the same time

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2786244B1 (en) 1998-11-24 2001-01-26 Snecma DIRECTLY CONTROLLED FUEL VALVE FOR FUEL FLOW INJECTION CIRCUIT
FR2916492B1 (en) * 2007-05-24 2009-07-17 Eurocopter France HYDRAULIC DISPENSER HAVING A GRIPPING DETECTION DEVICE
WO2014177942A2 (en) * 2013-03-14 2014-11-06 Pentair Valves & Controls UK Limited High integrity pressure protection system (hipps) manifold system and method
GB2522744B (en) * 2014-11-14 2016-03-16 Blagdon Actuation Res Ltd Servo actuators

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2004355A1 (en) * 1968-03-20 1969-11-21 Bishop Arthur
FR2099895A5 (en) * 1970-06-25 1972-03-17 Trw Inc
FR2352972A2 (en) * 1976-05-25 1977-12-23 Fairey Hydraulics IMPROVEMENTS IN HYDRAULIC SERVO-MECHANISMS
FR2460435A1 (en) * 1979-07-03 1981-01-23 Applic Mach Motrices HYDRAULIC DISPENSER, IN PARTICULAR FOR EQUIPPING AIRCRAFT AND HELICOPTER SERVO CONTROLS

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3482486A (en) * 1967-11-29 1969-12-09 United Aircraft Corp Redundant control method and apparatus
US3529514A (en) * 1969-03-25 1970-09-22 United Aircraft Corp Redundant servomechanism with bypass provisions
US3850196A (en) * 1973-11-05 1974-11-26 Gen Motors Corp Metering rod with position indicating means
FR2549167B1 (en) * 1983-07-13 1988-01-29 Applic Mach Motrices HYDRAULIC DISTRIBUTOR FOR EQUIPPING AN AIRCRAFT CONTROL
US4619288A (en) * 1985-11-06 1986-10-28 Pneumo Corporation Adjustable transducer and lock mechanism for monitoring valve position
FR2594515B1 (en) * 1986-02-19 1988-05-06 Snecma TRANSMISSION DEVICE WITH TWO DEGREES OF FREEDOM IN INPUT AND ONLY IN OUTPUT

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2004355A1 (en) * 1968-03-20 1969-11-21 Bishop Arthur
FR2099895A5 (en) * 1970-06-25 1972-03-17 Trw Inc
FR2352972A2 (en) * 1976-05-25 1977-12-23 Fairey Hydraulics IMPROVEMENTS IN HYDRAULIC SERVO-MECHANISMS
FR2460435A1 (en) * 1979-07-03 1981-01-23 Applic Mach Motrices HYDRAULIC DISPENSER, IN PARTICULAR FOR EQUIPPING AIRCRAFT AND HELICOPTER SERVO CONTROLS

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19926429A1 (en) * 1999-06-10 2000-12-14 Zf Luftfahrttechnik Gmbh Device for locking several actuators at the same time
US6676377B1 (en) 1999-06-10 2004-01-13 Zf Luftfahrttechnik Gmbh Device for simultaneously interlocking a plurality of actuators

Also Published As

Publication number Publication date
FR2747174A1 (en) 1997-10-10
US5899226A (en) 1999-05-04
FR2747174B1 (en) 1998-07-10

Similar Documents

Publication Publication Date Title
EP0021977B1 (en) Hydraulic directional valve, especially for servocontrols in aeroplanes and helicopters
EP0014643B1 (en) Water injection device for a steam iron, and relevant steam iron
EP0801232A1 (en) A hydraulic control valve for servo controlling an aircraft, especially helicopters
FR2567825A1 (en) DEVICE FOR CONTROLLING THE HYDRAULIC BRAKE PRESSURE OF VEHICLES WITH AN ANTI-BLOCKING DEVICE
FR2786242A1 (en) LOW AND HIGH PRESSURE SHUT-OFF VALVE
CA1302462C (en) Contact linkage for aerodyne flight controls
FR2520473A1 (en) SAFETY VALVE AND CONTROL DEVICE THEREOF
FR2468775A1 (en) HYDRAULIC DISTRIBUTOR
FR2739688A1 (en) QUICK-FITTING ROTATION DRIVE PIN, AND MACHINE COMPRISING SUCH A PIN
FR2701069A1 (en) Safety control device for controlled hydraulic cylinder.
EP0197858B1 (en) Height regulating device for the suspension unit of a heavy vehicle
EP0569288B1 (en) Helicopter tail rotor with a detector of exceeding a translational stress threshold in the pitch control
FR2596714A1 (en) BRAKE ASSIST MOTOR
FR2683295A1 (en) Apparatus for automatically fitting a seal into the valve (tap) spigot of a gas bottle (cylinder)
EP0054469B1 (en) Drum brake with braking force adjustment
EP1429946A1 (en) Tandem master cylinder for electrohydraulic braking system
FR2577638A1 (en) AUTOMATIC ADJUSTMENT APPARATUS FOR DISC BRAKE
FR2623163A1 (en) Hooking device intended to link two airborne elements with a given pre-stress
FR2757223A1 (en) Hydraulic installation used e.g. for vehicle braking system
FR2658254A1 (en) Device for locking a disc brake disc
FR2588516A1 (en) Device for assisting a control with two degrees of freedom for a gearbox
FR2596713A1 (en) BRAKE ASSIST MOTOR
FR2477241A1 (en) CONTROL VALVE FOR ACTUECHANISM ACTUATED BY FLUID PRESSURE
BE548753A (en)
BE523925A (en)

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE GB IT

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION HAS BEEN WITHDRAWN

18W Application withdrawn

Withdrawal date: 19980402