EP0284634A1 - Dispositif de positionnement électromécanique - Google Patents

Dispositif de positionnement électromécanique Download PDF

Info

Publication number
EP0284634A1
EP0284634A1 EP87104759A EP87104759A EP0284634A1 EP 0284634 A1 EP0284634 A1 EP 0284634A1 EP 87104759 A EP87104759 A EP 87104759A EP 87104759 A EP87104759 A EP 87104759A EP 0284634 A1 EP0284634 A1 EP 0284634A1
Authority
EP
European Patent Office
Prior art keywords
rod
housing
armature
end wall
actuator 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.)
Withdrawn
Application number
EP87104759A
Other languages
German (de)
English (en)
Inventor
Hans Klaus Dipl.-Ing. Teutsch
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.)
Moog GmbH
Original Assignee
Moog GmbH
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 Moog GmbH filed Critical Moog GmbH
Priority to EP87104759A priority Critical patent/EP0284634A1/fr
Publication of EP0284634A1 publication Critical patent/EP0284634A1/fr
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/06—Electromagnets; Actuators including electromagnets
    • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
    • H01F7/16—Rectilinearly-movable armatures
    • H01F7/1607—Armatures entering the winding
    • H01F7/1615—Armatures or stationary parts of magnetic circuit having permanent magnet
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/06—Electromagnets; Actuators including electromagnets
    • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
    • H01F7/16—Rectilinearly-movable armatures
    • H01F2007/1684—Armature position measurement using coils
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01F—MAGNETS; INDUCTANCES; TRANSFORMERS; SELECTION OF MATERIALS FOR THEIR MAGNETIC PROPERTIES
    • H01F7/00—Magnets
    • H01F7/06—Electromagnets; Actuators including electromagnets
    • H01F7/08—Electromagnets; Actuators including electromagnets with armatures
    • H01F7/121—Guiding or setting position of armatures, e.g. retaining armatures in their end position
    • H01F7/122—Guiding or setting position of armatures, e.g. retaining armatures in their end position by permanent magnets

Definitions

  • the invention relates to an electromechanical actuator according to the preamble of claim 1.
  • Such an actuator is known from DE-OS 32 41 254.
  • Actuators of the aforementioned type are used in particular to control hydraulic systems by means of valves. As a rule, they are required to have a linear relationship between the strength of the electrical excitation current supplied to the actuator and the mechanical adjustment caused by the actuator, with the greatest emphasis being placed on freedom from hysteresis between the current intensity and the mechanical adjustment.
  • the rod which moves as a function of the excitation current, protrudes on both sides from the housing of the actuator.
  • the spring arrangement against the action of which the armature and thus the rod is moved by the field of the excitation magnet, consists of two helical springs on both sides of the housing, which are supported between a housing wall and a ring fastened to the rod. These coil springs are therefore exposed to environmental influences. Even if the coil springs are centered around the rod in such a way that they do not touch the surface of the rod and therefore do not cause any friction there, hysteresis effects of the aforementioned type cannot be ruled out due to this construction of the spring arrangement.
  • Coil spring It is in the nature of one Coil spring, that changes its diameter during contraction and expansion, albeit slightly, so that the spring ends on the bearing surfaces on which they are supported carry out sliding movements in the radial direction.
  • sliding movements can only be carried out by overcoming static friction forces, which explains the above-mentioned hysteresis effects, which lead to a non-linearity in connection with the excitation current and the mechanical adjustment of the actuator armature.
  • the invention is therefore based on the object of specifying an electromechanical actuator of the type mentioned, in which a hysteresis between the excitation current and the mechanical movement of the moving element is minimized.
  • the spring arrangement accordingly consists of a substantially flat spring washer, which is fastened to the moving rod and to the fixed housing of the actuator and which is designed such that it is subjected to torsion, with no friction between the spring and parts, on which the spring washer is supported.
  • the spring is preferably provided with a sleeve in its center, which is fastened to the rod, preferably screwed onto the rod, and from which the spring washer stands freely.
  • the outer edge of the spring washer is expediently between in the housing one of the end walls, which delimit the chamber accommodating the piston, and is clamped in the housing, preferably with the interposition of a spacer ring, so that the spring washer is clamped uniformly over its entire circumference.
  • the friction effects are further reduced if the necessary movable support of the rod in the housing is carried out by means of a ball bearing.
  • the spring washer itself contributes to supporting the rod in the radial direction, which is a particular advantage because this support is free of any sliding friction.
  • the invention can also be used in an electromechanical actuator which contains at least two permanent magnets which are able to hold the armature in one of the end positions, even if the excitation current through the magnet coil is switched off.
  • the housing 1 shows a housing 1 of essentially circular cross section.
  • the housing 1 has one cylindrical shell 2, which at one end merges into a perpendicular end wall 3.
  • the housing 1 is closed by a cover 4.
  • the housing is fastened by means of bolts 5, one of which is shown in the drawing, on the body 6 of a unit (not shown) to be influenced by the actuator, with the interposition of an elastic sealing ring 7, the cover 4 resting on the body 6 and is partially pressed into the cylindrical housing 1 by tightening the bolts 5.
  • end walls 8 and 9 are inserted, which are held at a mutual distance by a sleeve 10 made of magnetically permeable material.
  • the end walls 8 and 9 have a substantially circular outline and are supported on the inner wall of the housing shell 2. They each have an essentially trapezoidal shape in axial section and are each provided in the middle with a bore 11 which is penetrated by a hollow rod 12.
  • the hollow rod 12 carries on the section lying approximately in the middle of the housing 1 an anchor 13 made of magnetically permeable material, which is attached to the rod 12.
  • This anchor is located in a chamber 14 which is delimited by the end walls 8 and 9.
  • an intermediate space is formed between the end faces 13a and 13b thereof and the sections 8a and 9a of the end walls 8 and 9 opposite them. These spaces allow the armature 13 to move in the axial direction.
  • this carries an external thread 12a, onto which a bushing 15, which is provided with an internal thread, is screwed, which is firmly connected to an essentially circular spring washer 16.
  • the bushing 15 and the spring washer 16 can be formed in one piece, but the spring washer can also be fastened to the bushing 15 by suitable mechanical measures, such as flanging, soldering, welding or the like.
  • the bush 15 with the spring washer 16 is fixed on the rod 12 by a lock nut 17 which is screwed onto the thread 12a.
  • the spring washer 16 bears on its outer edge region against a spacer ring 18 which lies in the throat at the transition between the cylindrical jacket 2 and the end wall 3 of the housing 1.
  • the edge region of the spring washer 16 bears against an edge 9b of the second end wall 9 which projects in the axial direction.
  • the pressure force caused by them is transmitted via the cover 4, the edge of the first end wall 8, the sleeve 10 and the edge of the second end wall 9 to the edge region of the spring washer 16, so that it is between the axially projecting edge 9b and the spacer ring 18 is clamped.
  • the spring washer 16 is relaxed.
  • a first annular permanent magnet 19 is mounted radially outside the armature 13 on a shoulder of the first end wall 8 and is polarized in the axial direction. This extends partially over the armature 13.
  • An annular pole piece 20 adjoins it in the axial direction.
  • a second permanent magnet 21, which is polarized opposite to the first permanent magnet is attached, in the axial direction Connects an annular pole piece 22 in the direction.
  • a resilient spacer ring 23 which presses the pole pieces against the associated permanent magnet rings 19 and 21, respectively.
  • the permanent magnets 19 and 21 can be glued to the end walls 8 and 9 and the pole pieces can also be glued to the associated permanent magnets, so that the spacer ring 23 can be omitted if necessary.
  • the permanent magnets, the pole pieces and the spacer ring delimit the aforementioned chamber 14 in the radial direction.
  • the aforementioned arrangement surrounds an excitation coil 24, the connecting lines 25 of which extend through openings in the first end wall 8, the cover 4 and the body 6.
  • the sleeve 10 closes the magnetic circuit that can be generated by the excitation coil 24 outside the excitation coil 24.
  • the hollow rod 12 has an internally threaded section into which a threaded adjusting rod 26 is screwed.
  • a lock nut 27 is screwed onto the end of the adjusting rod 26 protruding from the rod 12.
  • the end section of the rod 12 with the end of the adjusting rod 26 and the lock nut screwed onto it extend into a tubular collar 28 formed on the housing end wall 3, which is closed off by a removable closure cap 29.
  • the rod 12 is supported at its left end in the cover 4 of the housing by means of a ball bearing 30 so as to be axially movable. Between the adjusting rod 26 and the inner wall The hollow rod 12 is an annular space 31, from which bores 32 extend in the wall of the rod 12 and through which a damping fluid can be guided into the cavity enclosed by the housing 1.
  • first and second end walls 8 and 9 are made of a magnetically permeable material.
  • the housing 1 has no influence on the magnetic circuit and can be made of any material.
  • the housing can be partially omitted.
  • a design can also be selected in which the end walls 8 and 9 are clamped to the body 6 together with the sleeve 10 arranged therebetween by means of tension screws which extend over the entire arrangement, end wall 3 and cover 4 are replaced by washers.
  • the sleeve 10 can expediently be constructed from two rings, at the joint of which the connecting lines 25 of the excitation coil 24 emerge.
  • Fig. 2 shows the spring washer 16 in plan view. In the middle of the spring washer, the bushing 15 provided with the internal thread can be seen. As can also be seen from FIG. 2, two slots 16a are formed in the spring washer 16, which run in a spiral shape and in the present case are arranged offset from one another by 180 °. It should be noted that more such slots 16a can also be formed, for example three slots which are each offset by 120 ° from one another. Because of these slots 16a, the edge region of the spring washer 16 can be in relation to the bush 15 in the axial direction of the overall arrangement, ie 2 are moved elastically perpendicular to the plane of the drawing, with the intermediate sections which connect the edge region to the center of the spring washer undergoing a torsion.
  • the spring washer 16 on the rod 12 can be adjusted so that in the relaxed state of the spring washer 16, the armature 13 is located in the middle between the two sections 8a and 9a of the end walls 8 and 9, forming air gaps of the same width .
  • This position can be adjusted by screwing the rod into the thread of the bushing 15. This position is then fixed using the lock nut 17.
  • the electromechanical actuator i.e.
  • an adjustment of the position of the armature with respect to the unit (not shown) in the body 6 can be achieved in the body 6 by means of the adjusting rod 26, which after removing the cap 29 and loosening the lock nut 27 by twisting can be adjusted in a suitable manner, whereupon the lock nut 27 is tightened again and the cap 29 is replaced.
  • the assembly of the actuator shown is very simple.
  • the individual parts shown are inserted one after the other into the housing 1, starting with the spacer ring 18.
  • Subassembly pre-assembled from the rod 12, spring washer 16 and armature 13 is then inserted into the housing 1. Possibly.
  • the magnetic ring 21 and the pole piece 22 can also already be attached to the end wall 9.
  • the field coil 24 and the spacer sleeve 10 are then inserted, after which the first end wall 8, which may already be theirs Permanent magnet 19 and the pole piece 20 carries, with the interposition of the spacer ring 23 inserted into the housing 1.
  • the lid 4 is pushed onto the rod 12. This overall arrangement is then fastened to the body 6 by means of the bolts 5.
  • the spring washer 16 with the bush 15 and then the second end wall 9 can be inserted, whereupon the rod 12 with the armature 13 is screwed into the bush. The rest of the assembly then takes place as previously described. It should be emphasized that, with the exception of the fastening of the spring ring on the rod 12, no parts within the housing 1 need to be firmly connected to one another.
  • the rod 26 with the lock nut 27 is only a particularly advantageous embodiment. It can be dispensed with if the rod 12 is connected directly to the unit to be actuated.
  • the armature 13 is shifted with the rod 12 to the left or right by excitation of the coil 24 by means of a direct current, depending on the current direction and current strength, the one air gap between the one end face of the armature and the opposite section of the one end wall being smaller and the corresponding one Air gap on the other side of the armature increases.
  • the spring washer 16 bends without rubbing against any object.
  • the ball bearing of the rod 12 at 30 reduces the effects of friction to a minimum.
  • the magnetic circuit generated by the excitation coil 24 continues torically around the coil 24 through the sleeve 10 made of magnetically permeable material through one end wall, the anchor and the other end wall.
  • annular permanent magnets 19 and 21 with associated pole pieces 20 and 22 are arranged in the electromechanical actuator, which cause the armature to be held in each of the end positions that it reaches at maximum deflection, even if no current flows through the excitation coil 24. If this effect is not desired, the permanent magnet rings 19 and 21 and the pole pieces 20 and 22 connected to them and the spacer ring 23 are to be omitted.
  • the entire interior of the electromechanical actuator can be filled with a fluid from the outside and can be connected to an external fluid circuit.
  • This fluid causes damping of the movement of the armature in the actuator, which prevents overshoots and bouncing.
  • the fluid can be a suitable oil.
  • the spring arrangement is very flat due to the disc-shaped design of the spring and is protected against environmental influences, since it is arranged in the housing of the actuator. It is Another advantage is that the actuator can be adjusted independently of the unit to be controlled even after complete assembly.

Landscapes

  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Reciprocating, Oscillating Or Vibrating Motors (AREA)
  • Fluid-Damping Devices (AREA)
EP87104759A 1987-03-31 1987-03-31 Dispositif de positionnement électromécanique Withdrawn EP0284634A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP87104759A EP0284634A1 (fr) 1987-03-31 1987-03-31 Dispositif de positionnement électromécanique

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP87104759A EP0284634A1 (fr) 1987-03-31 1987-03-31 Dispositif de positionnement électromécanique

Publications (1)

Publication Number Publication Date
EP0284634A1 true EP0284634A1 (fr) 1988-10-05

Family

ID=8196885

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87104759A Withdrawn EP0284634A1 (fr) 1987-03-31 1987-03-31 Dispositif de positionnement électromécanique

Country Status (1)

Country Link
EP (1) EP0284634A1 (fr)

Cited By (10)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0373383A1 (fr) * 1988-12-16 1990-06-20 Robert Bosch Gmbh Régulateur de vitesse pour moteurs à combustion interne à injection de combustible
EP0569669A1 (fr) * 1992-03-16 1993-11-18 Robert Bosch Gmbh Moteur linéaire électromagnétique à double effet
EP0576813A1 (fr) * 1992-05-29 1994-01-05 THOMAS MAGNETE GmbH Electro aimant comprenant une tige à aimant en plastique
EP0736882A1 (fr) * 1995-04-07 1996-10-09 Appareillages Electro-Mecaniques Du Faucigny Dispositif de commande à électroaimant à noyau sans frottement et application aux vannes à commande continue
WO2000023740A1 (fr) * 1998-10-16 2000-04-27 Oglesby & Butler Research & Development Limited Une vanne
EP1382907A1 (fr) * 2002-07-12 2004-01-21 G. Kromschröder Aktiengesellschaft Dispositif pour régler le débit de gaz dans un brûleur
WO2012041550A1 (fr) * 2010-10-01 2012-04-05 Contitech Vibration Control Gmbh Actionneur
US9620274B2 (en) 2015-02-17 2017-04-11 Enfield Technologies, Llc Proportional linear solenoid apparatus
EP3454349A1 (fr) * 2017-09-07 2019-03-13 Rausch und Pausch GmbH Procédé de fabrication d'un raccordement induit magnétique-poussoir et raccordement induit magnétique-poussoir pour un actionneur linéaire
DE102019203949B3 (de) * 2019-03-22 2020-09-03 Magna powertrain gmbh & co kg Elektromagnet

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4127835A (en) * 1977-07-06 1978-11-28 Dynex/Rivett Inc. Electromechanical force motor
FR2410344A1 (fr) * 1977-11-25 1979-06-22 Garrett Corp Electro-vanne, notamment electro-vanne rapide a trois voies, a centre ferme
FR2417881A1 (fr) * 1978-02-20 1979-09-14 Jidosha Kiki Co Convertisseurs electromecaniques et dispositifs de commande pour directions mecaniques les utilisant
FR2516698A1 (fr) * 1981-11-16 1983-05-20 Moog Inc Actionneur electromecanique, notamment pour electrovannes
US4463332A (en) * 1983-02-23 1984-07-31 South Bend Controls, Inc. Adjustable, rectilinear motion proportional solenoid
EP0157631A2 (fr) * 1984-04-04 1985-10-09 Parker Hannifin Corporation Valve electromagnétique

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4127835A (en) * 1977-07-06 1978-11-28 Dynex/Rivett Inc. Electromechanical force motor
FR2410344A1 (fr) * 1977-11-25 1979-06-22 Garrett Corp Electro-vanne, notamment electro-vanne rapide a trois voies, a centre ferme
FR2417881A1 (fr) * 1978-02-20 1979-09-14 Jidosha Kiki Co Convertisseurs electromecaniques et dispositifs de commande pour directions mecaniques les utilisant
FR2516698A1 (fr) * 1981-11-16 1983-05-20 Moog Inc Actionneur electromecanique, notamment pour electrovannes
US4463332A (en) * 1983-02-23 1984-07-31 South Bend Controls, Inc. Adjustable, rectilinear motion proportional solenoid
EP0157631A2 (fr) * 1984-04-04 1985-10-09 Parker Hannifin Corporation Valve electromagnétique

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN, Band 9, Nr. 102 (E-312)[1825], 4. Mai 1985; & JP-A-59 228 702 (TOKYO DENKI K.K.) 22-12-1984 *

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0373383A1 (fr) * 1988-12-16 1990-06-20 Robert Bosch Gmbh Régulateur de vitesse pour moteurs à combustion interne à injection de combustible
EP0569669A1 (fr) * 1992-03-16 1993-11-18 Robert Bosch Gmbh Moteur linéaire électromagnétique à double effet
EP0576813A1 (fr) * 1992-05-29 1994-01-05 THOMAS MAGNETE GmbH Electro aimant comprenant une tige à aimant en plastique
US5402093A (en) * 1992-05-29 1995-03-28 Thomas Magnete Gmbh Electromagnet having an armature with an injection-molded guide or control rod
EP0736882A1 (fr) * 1995-04-07 1996-10-09 Appareillages Electro-Mecaniques Du Faucigny Dispositif de commande à électroaimant à noyau sans frottement et application aux vannes à commande continue
FR2732814A1 (fr) * 1995-04-07 1996-10-11 Appareillages Electro Mecaniqu Dispositif de commande a electroaimant a noyau sans frottement, et application aux vannes a commande continue
WO2000023740A1 (fr) * 1998-10-16 2000-04-27 Oglesby & Butler Research & Development Limited Une vanne
EP1382907A1 (fr) * 2002-07-12 2004-01-21 G. Kromschröder Aktiengesellschaft Dispositif pour régler le débit de gaz dans un brûleur
WO2012041550A1 (fr) * 2010-10-01 2012-04-05 Contitech Vibration Control Gmbh Actionneur
US9172277B2 (en) 2010-10-01 2015-10-27 Contitech Vibration Control Gmbh Actuator
US9620274B2 (en) 2015-02-17 2017-04-11 Enfield Technologies, Llc Proportional linear solenoid apparatus
US9704636B2 (en) 2015-02-17 2017-07-11 Enfield Technologies, Llc Solenoid apparatus
EP3454349A1 (fr) * 2017-09-07 2019-03-13 Rausch und Pausch GmbH Procédé de fabrication d'un raccordement induit magnétique-poussoir et raccordement induit magnétique-poussoir pour un actionneur linéaire
US11097608B2 (en) 2017-09-07 2021-08-24 Rapa Automotive Gmbh & Co. Kg Method for manufacturing a solenoid-armature ram composite and a solenoid-armature ram composite for a linear actuator
DE102019203949B3 (de) * 2019-03-22 2020-09-03 Magna powertrain gmbh & co kg Elektromagnet

Similar Documents

Publication Publication Date Title
DE102006011078B4 (de) Hubmagnet sowie Verfahren zu seiner Herstellung
WO2010086058A1 (fr) Aimant proportionnel pour un distributeur hydraulique et son procédé de fabrication
DE4137821A1 (de) Hydraulischer, regelbarer schwingungsdaempfer
EP3409984B1 (fr) Distributeur à tiroir cylindrique
DE3823430A1 (de) Hydraulischer teleskopstossdaempfer
EP1217209B1 (fr) Dispositif de commande pour une machine hydrostatique à débit variable
DE4012524A1 (de) Feststellvorrichtung fuer eine linearbewegungseinheit
DE68916435T2 (de) Schnell ansprechendes, druckausgeglichenes, elektromagnetisches hochdruck-steuerventil.
EP0284634A1 (fr) Dispositif de positionnement électromécanique
DE3405315A1 (de) Regelbarer schwingungsdaempfer fuer fahrzeuge
DE3635894A1 (de) Stossdaempfer
DE2458516A1 (de) Elektromagnetische betaetigungseinrichtung
EP1760796A1 (fr) Dispositif comprenant un élément à mémoire de forme
DE10114472A1 (de) Elektromagnet zum Antrieb eines hydraulischen Ventils
DE4100950A1 (de) Hydraulische kupplungsbetaetigungseinrichtung
DE102020134123A1 (de) Elektromagnetisches Druckregelventil
DE3510601A1 (de) Kolbeneinheit fuer einen arbeitszylinder mit einer einrichtung zum erfassen der kolbenposition
EP1377732A1 (fr) Connexion entre une extremite de tige d'une soupape d'echange gazeux dans un moteur a combustion interne et un piston de reglage en forme de douille d'un actionneur de soupape
EP0251075A2 (fr) Electrovanne pour fluides liquides et gazeux
EP3070721B1 (fr) Dispositif d'actionnement
DE19502671A1 (de) Elektromagnetantrieb, insbesondere für Elektromagnetventile als Stellglieder für Fluide
DE2361591A1 (de) Schieberventil zur steuerung des arbeitsdrucks eines arbeitsmediums
DE9305640U1 (de) Druckmittelbetätigter Arbeitszylinder
WO1997018568A1 (fr) Systeme d'electro-aimant de levage
DE69517308T2 (de) Magnetischer betätiger mit mehrfach luftspalten

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): AT BE CH DE ES FR GB GR IT LI LU NL SE

ITCL It: translation for ep claims filed

Representative=s name: ADRIANO DALLA ROSA

GBC Gb: translation of claims filed (gb section 78(7)/1977)
17P Request for examination filed

Effective date: 19890214

RBV Designated contracting states (corrected)

Designated state(s): DE FR GB IT

17Q First examination report despatched

Effective date: 19910123

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

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19910806

RIN1 Information on inventor provided before grant (corrected)

Inventor name: TEUTSCH, HANS KLAUS, DIPL.-ING.