CA2018965A1 - Electromagnetic actuator arrangement - Google Patents
Electromagnetic actuator arrangementInfo
- Publication number
- CA2018965A1 CA2018965A1 CA 2018965 CA2018965A CA2018965A1 CA 2018965 A1 CA2018965 A1 CA 2018965A1 CA 2018965 CA2018965 CA 2018965 CA 2018965 A CA2018965 A CA 2018965A CA 2018965 A1 CA2018965 A1 CA 2018965A1
- Authority
- CA
- Canada
- Prior art keywords
- electromagnetic actuator
- winding
- energised
- current
- capacitor
- 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.)
- Abandoned
Links
- 238000004804 winding Methods 0.000 claims abstract description 26
- 239000003990 capacitor Substances 0.000 claims description 17
- 239000004020 conductor Substances 0.000 claims description 5
- 239000004065 semiconductor Substances 0.000 claims description 5
- 239000007779 soft material Substances 0.000 claims description 4
- 230000001419 dependent effect Effects 0.000 claims 1
- 101100365087 Arabidopsis thaliana SCRA gene Proteins 0.000 abstract 1
- 101150105073 SCR1 gene Proteins 0.000 abstract 1
- 101100134054 Saccharomyces cerevisiae (strain ATCC 204508 / S288c) NTG1 gene Proteins 0.000 abstract 1
- 238000001514 detection method Methods 0.000 abstract 1
- 230000005389 magnetism Effects 0.000 abstract 1
- 230000004907 flux Effects 0.000 description 4
- 230000002441 reversible effect Effects 0.000 description 4
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000007935 neutral effect Effects 0.000 description 2
- 101100536354 Drosophila melanogaster tant gene Proteins 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 230000003190 augmentative effect Effects 0.000 description 1
- 230000000881 depressing effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000009499 grossing Methods 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000003534 oscillatory effect Effects 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H71/00—Details of the protective switches or relays covered by groups H01H73/00 - H01H83/00
- H01H71/10—Operating or release mechanisms
- H01H71/12—Automatic release mechanisms with or without manual release
- H01H71/24—Electromagnetic mechanisms
- H01H71/2454—Electromagnetic mechanisms characterised by the magnetic circuit or active magnetic elements
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H83/00—Protective switches, e.g. circuit-breaking switches, or protective relays operated by abnormal electrical conditions otherwise than solely by excess current
- H01H83/14—Protective switches, e.g. circuit-breaking switches, or protective relays operated by abnormal electrical conditions otherwise than solely by excess current operated by imbalance of two or more currents or voltages, e.g. for differential protection
- H01H83/144—Protective switches, e.g. circuit-breaking switches, or protective relays operated by abnormal electrical conditions otherwise than solely by excess current operated by imbalance of two or more currents or voltages, e.g. for differential protection with differential transformer
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01H—ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
- H01H47/00—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current
- H01H47/02—Circuit arrangements not adapted to a particular application of the relay and designed to obtain desired operating characteristics or to provide energising current for modifying the operation of the relay
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Engineering & Computer Science (AREA)
- Power Engineering (AREA)
- Breakers (AREA)
- Electromagnets (AREA)
- Reciprocating, Oscillating Or Vibrating Motors (AREA)
- Driving Mechanisms And Operating Circuits Of Arc-Extinguishing High-Tension Switches (AREA)
Abstract
ABSTRACT
Electromagnetic Actuator Arrangement A residual current circuit breaker comprising a switch (SW1) biased open by a biasing spring (SP) and operated by a yoke (Y1) which attracts an armature (AR1) when its winding (L1) is energised is provided with means (C1, SCR1) for instantaneously reversing the magnetising force acting on the armature when the winding (L1) is de-energised in response to the detection of a fault current. As a result, the residual magnetism in the armature (AR1) is opposed by the reversed magnetic field from the winding (L1) and the tendency of the armature to stick to the yoke is avoided. Consequently, the tripping time is reduced.
Electromagnetic Actuator Arrangement A residual current circuit breaker comprising a switch (SW1) biased open by a biasing spring (SP) and operated by a yoke (Y1) which attracts an armature (AR1) when its winding (L1) is energised is provided with means (C1, SCR1) for instantaneously reversing the magnetising force acting on the armature when the winding (L1) is de-energised in response to the detection of a fault current. As a result, the residual magnetism in the armature (AR1) is opposed by the reversed magnetic field from the winding (L1) and the tendency of the armature to stick to the yoke is avoided. Consequently, the tripping time is reduced.
Description
h'~
_LECTROMAGNETIC ACTUATOR ARRANGEMENT__________________________________ The present invention relates to electromagnetic a_~uator arrangements and relates particularly but no-t exclusively to residual current circuit breakers.
It is necessary for residual current circuit breakers in particular to trip very quickly, e.g. in less than 20 milliseconds. In order to meet this requirement, it has been necessary to provide a very powerful biasing spring which trips the actuator when the actua-tor is de-energised. A correspondingly powerful and bulky electromagnet has been required to overcome the spring bias in the energised condition.
An object of the present invention is to provide an electromagnetic actuator arrangement which is faster-acting and/or requires a less powerful electromagnet than comparable conventional actuator arrangements.
According to the present invention, an electromagnetic actuator arrangement comprises an electromagnetic actuator, including at least one operating member of magnetically soft material which cooperates with biasing means and is magnetised when said electromagnetic actuator is energised and means for reversing the magnetising force acting on said operating em'3-er when the said electromagnetic actuator is de-energised.
The invention is applicable particularly but not exclusively to circuit breakers and relays, which incorporate -two such operating members, namely a fixed yoke and a movable armature. By reversing the magnetising force on de-energising an electromagnet actuator of this type, the residual magnetic flux in the armature is opposed by the reversed magnetic field and the normal tenden_y of the armature to stick to the yoke immediately after the winding has been de-energised is avoided.
In fact during the brief period in which the residual magnetic flux in -the armature maintains its original polarity, the armature is repelled by the reversed magnetic field arising from the reversed magnetising force and thus the biasing force is briefly augmented at -the instant of de-energising the winding.
Accordingly -the invention is also applicable -for example to solenoids and other devices which incorporate only a single "opera-ting member" of magnetically soft material.
In typical preferred embodiments, particularly of relay and circuit-breaker arrangements, the armature will be removed from the magnetic field of the winding by the biasing means by the time that the residual magnetic flux in the armature has been reversed by the reversal of magnetising force on de-energising the actuator. The resulting force of attraction acting on the armature will accordingly be very weak in comparison with the opposing biasing force and the tripping time will not be adversely affected.
A particularly convenient way of limiting the reverse magnetisation is to reverse the magnetising force by means of a capacitor (which may for example by connected in parallel with the winding) which is arranged to discharge through the winding on de-energisation of the actuator. Preferably the discharge is oscillatory so that the residual magnetisation of the armature is thereby reduced to a very low level.
In a preferred embodiment the winding of the electromagnetic actuator is energised from a current force (preferably a substantial~ c~n~tant current source) and a gate-controlled semi-conductor switching device is arranged both to bypass current from said current source in response to a control signal applied 6~
to the ga-te of said device on de-energising said electromagnetic actuator, and to conduct the current which is disch~rged by said capacitor through said winding.
A preferred embodiment of the invention is described below by way of example only with reference to the accompanying drawing, Figure 1, which is a ci~cuit diagram of a residual current circuit breaker in accordance with the invention.
The circuit shown in Figure 1 comprises live (L) and neutral (N) mains input terminals which are connected via a two-pole swi-tch SWl to mains output terminals, which may in turn be connected to an electrical appliance (not shownj. Switch SWl is controlled by an electromagnetic actuator comprising a movable armature ARl and a yoke Yl which is provided with a winding Llo Armature ARl is mechanically linked to switch SWl and the latter is biased open by a tension spring SP which acts on the armature. Armature ARl and yoke Yl are composed of magnetically soft iron and contact one another when switch SWl is closed.
In use, switch SWl is closed manually and energised by a rectified constant current source comprising a series-connected diode Dl, resistors R3, R4 and R5 and R6 and capacitor C6 (which are connected between the mains conductors) and resistor R2 (which is connected between -the junction of R3 and C6 and one end of winding Ll).
The other end of winding Ll is connected to pin 6 of an RA3783 integrated circuit ICl ad thence via pin 4 thereof to the free terminal of smoothing capacitor C6.
Accordingly winding Ll is energised a~.d maintains switch SWl ON.
A ferrite-core transformer Tl is coupled to the 35 mains conductors and its output is fed to pins 2 and 3 of ICl.
_LECTROMAGNETIC ACTUATOR ARRANGEMENT__________________________________ The present invention relates to electromagnetic a_~uator arrangements and relates particularly but no-t exclusively to residual current circuit breakers.
It is necessary for residual current circuit breakers in particular to trip very quickly, e.g. in less than 20 milliseconds. In order to meet this requirement, it has been necessary to provide a very powerful biasing spring which trips the actuator when the actua-tor is de-energised. A correspondingly powerful and bulky electromagnet has been required to overcome the spring bias in the energised condition.
An object of the present invention is to provide an electromagnetic actuator arrangement which is faster-acting and/or requires a less powerful electromagnet than comparable conventional actuator arrangements.
According to the present invention, an electromagnetic actuator arrangement comprises an electromagnetic actuator, including at least one operating member of magnetically soft material which cooperates with biasing means and is magnetised when said electromagnetic actuator is energised and means for reversing the magnetising force acting on said operating em'3-er when the said electromagnetic actuator is de-energised.
The invention is applicable particularly but not exclusively to circuit breakers and relays, which incorporate -two such operating members, namely a fixed yoke and a movable armature. By reversing the magnetising force on de-energising an electromagnet actuator of this type, the residual magnetic flux in the armature is opposed by the reversed magnetic field and the normal tenden_y of the armature to stick to the yoke immediately after the winding has been de-energised is avoided.
In fact during the brief period in which the residual magnetic flux in -the armature maintains its original polarity, the armature is repelled by the reversed magnetic field arising from the reversed magnetising force and thus the biasing force is briefly augmented at -the instant of de-energising the winding.
Accordingly -the invention is also applicable -for example to solenoids and other devices which incorporate only a single "opera-ting member" of magnetically soft material.
In typical preferred embodiments, particularly of relay and circuit-breaker arrangements, the armature will be removed from the magnetic field of the winding by the biasing means by the time that the residual magnetic flux in the armature has been reversed by the reversal of magnetising force on de-energising the actuator. The resulting force of attraction acting on the armature will accordingly be very weak in comparison with the opposing biasing force and the tripping time will not be adversely affected.
A particularly convenient way of limiting the reverse magnetisation is to reverse the magnetising force by means of a capacitor (which may for example by connected in parallel with the winding) which is arranged to discharge through the winding on de-energisation of the actuator. Preferably the discharge is oscillatory so that the residual magnetisation of the armature is thereby reduced to a very low level.
In a preferred embodiment the winding of the electromagnetic actuator is energised from a current force (preferably a substantial~ c~n~tant current source) and a gate-controlled semi-conductor switching device is arranged both to bypass current from said current source in response to a control signal applied 6~
to the ga-te of said device on de-energising said electromagnetic actuator, and to conduct the current which is disch~rged by said capacitor through said winding.
A preferred embodiment of the invention is described below by way of example only with reference to the accompanying drawing, Figure 1, which is a ci~cuit diagram of a residual current circuit breaker in accordance with the invention.
The circuit shown in Figure 1 comprises live (L) and neutral (N) mains input terminals which are connected via a two-pole swi-tch SWl to mains output terminals, which may in turn be connected to an electrical appliance (not shownj. Switch SWl is controlled by an electromagnetic actuator comprising a movable armature ARl and a yoke Yl which is provided with a winding Llo Armature ARl is mechanically linked to switch SWl and the latter is biased open by a tension spring SP which acts on the armature. Armature ARl and yoke Yl are composed of magnetically soft iron and contact one another when switch SWl is closed.
In use, switch SWl is closed manually and energised by a rectified constant current source comprising a series-connected diode Dl, resistors R3, R4 and R5 and R6 and capacitor C6 (which are connected between the mains conductors) and resistor R2 (which is connected between -the junction of R3 and C6 and one end of winding Ll).
The other end of winding Ll is connected to pin 6 of an RA3783 integrated circuit ICl ad thence via pin 4 thereof to the free terminal of smoothing capacitor C6.
Accordingly winding Ll is energised a~.d maintains switch SWl ON.
A ferrite-core transformer Tl is coupled to the 35 mains conductors and its output is fed to pins 2 and 3 of ICl.
2 ~
The potential difference across pins 2 and 3 is monltored by ICl and in the event that it exceeds a predetermined threshold value (as a result of an inbalance in the forward and return currents in the mains conductors due to a potentially dangereous leakage of current to earth) an output voltage is generated at pin 5. ~ series-corrected discharge capacitator Cl and thyris-tor SCRl are corrected in parallel with winding Ll and the ~ate of SCRl is connected to pin S. The cathode of thyristor SCRl is also connected to the negative terminal of capaci-tor C6 so that thyristor SCRl bypasses the output current of the curren-t source as well as providing a discharge path for capacitor Cl through winding Ll. The current from R2 is sufficient to hold SCRl ON whilst capacitor Cl is discharging.
Accordingly, when an earth leakage current is detected, a voltage appears at terminal 5 of ICl which fires thyristor SCRl, thereby bypassing the forward current from resistor R2 of the current source and allowing capacitor Cl to send a brief reverse discharge curren-t through winding Ll which generates a reverse magnetising force which opposes the residual flux in ~rm2ture ARl and yoke Yl. Accordingly, armature ARl is immedia-tely repelled from yoke ~1 and is rapidly removed from the yoke by biasing spring SP. By this time, the current in winding Ll has fallen to zero. Thus switch SWl breaks the mains circuit very rapidly.
I~hen safe conditions have been restored, the circuit may be re-set by depressing switch SWl manually.
A pair of test contacts TC are connected in series with a resistor R7 between the neutral output terminal and a live input terminal of the mains conductors to enable a residual current to be generated artificially in order to test the circuit.
~ .. ?
The sensitivity of the circuit can be adjusted by altering the value oF a resis-tor R8 which is connected across the winding of Tl or the value of resistor Rl which is connected between terminals 1 and 7 of ICl. It is by-passed by a noise suppression capacitor C4 and an additional noise-suppression capacitor C3 is connected between pins 1 and 8 of ICl. Resistor R8 is by-passed by a noise-suppression capacitor C5 and a noise-suppression capacitor C2 is also connected between -the gate and cathode of thyristor SCRl.
It should be noted that the circuit au-tomatically switches switch SWl OFF in the event of loss oE mains supply.
The potential difference across pins 2 and 3 is monltored by ICl and in the event that it exceeds a predetermined threshold value (as a result of an inbalance in the forward and return currents in the mains conductors due to a potentially dangereous leakage of current to earth) an output voltage is generated at pin 5. ~ series-corrected discharge capacitator Cl and thyris-tor SCRl are corrected in parallel with winding Ll and the ~ate of SCRl is connected to pin S. The cathode of thyristor SCRl is also connected to the negative terminal of capaci-tor C6 so that thyristor SCRl bypasses the output current of the curren-t source as well as providing a discharge path for capacitor Cl through winding Ll. The current from R2 is sufficient to hold SCRl ON whilst capacitor Cl is discharging.
Accordingly, when an earth leakage current is detected, a voltage appears at terminal 5 of ICl which fires thyristor SCRl, thereby bypassing the forward current from resistor R2 of the current source and allowing capacitor Cl to send a brief reverse discharge curren-t through winding Ll which generates a reverse magnetising force which opposes the residual flux in ~rm2ture ARl and yoke Yl. Accordingly, armature ARl is immedia-tely repelled from yoke ~1 and is rapidly removed from the yoke by biasing spring SP. By this time, the current in winding Ll has fallen to zero. Thus switch SWl breaks the mains circuit very rapidly.
I~hen safe conditions have been restored, the circuit may be re-set by depressing switch SWl manually.
A pair of test contacts TC are connected in series with a resistor R7 between the neutral output terminal and a live input terminal of the mains conductors to enable a residual current to be generated artificially in order to test the circuit.
~ .. ?
The sensitivity of the circuit can be adjusted by altering the value oF a resis-tor R8 which is connected across the winding of Tl or the value of resistor Rl which is connected between terminals 1 and 7 of ICl. It is by-passed by a noise suppression capacitor C4 and an additional noise-suppression capacitor C3 is connected between pins 1 and 8 of ICl. Resistor R8 is by-passed by a noise-suppression capacitor C5 and a noise-suppression capacitor C2 is also connected between -the gate and cathode of thyristor SCRl.
It should be noted that the circuit au-tomatically switches switch SWl OFF in the event of loss oE mains supply.
Claims (11)
1. An electromagnetic actuator arrangement comprising an electromagnetic actuator, including at least one operating member of magnetically soft material which cooperates with biasing means and is magnet when said electromagnetic actuator is energised and comprising means for reversing the magnetising force acting on said operating member when the said electromagnetic actuator is de-energised.
2. An electromagnetic actuator arrangement as claimed in claim 1 comprising two operating members of magnetically soft material which are mutually attracted when said electromagnetic actuator is energised, said operating members being relatively movable and being biased apart by said biasing means which operates said electromagnetic actuator when it is de-energised.
3. An electromagnetic actuator arrangement as claimed in claim 1 or claim 2 wherein said magnetising force reversing means comprises means for reversing the flow of current in a winding which is magnetically coupled to said operating member(s).
4. An electromagnetic actuator arrangement as claimed in claim 3 wherein said current flow reversing means includes a capacitor which discharges through said winding on de-energising said electromagnetic actuator.
5. An electromagnetic actuator arrangement as claimed in any preceding claim wherein a said operating member is arranged to be removed by said biasing means from a magnetic field of the electromagnetic actuator on reversing said magnetising force.
6. An electromagnetic actuator arrangement as claimed in any preceding claim wherein said electromagnetic actuator is arranged to operate at least one pair of electric contacts.
7. An electromagnetic actuator arrangement as claimed in claim 6 wherein said electromagnetic actuator is a mains circuit breaker.
8. An electromagnetic actuator arrangement as claimed in claim 7 which is a residual current circuit breaker and comprises means for detecting residual current in a mains circuit and means responsive to said residual current to de-energise said electromagnetic actuator, said electric contacts being arranged to break said mains circuit on de-energising said electromagnetic actuator.
9. An electromagnetic actuator arrangement as claimed in claim 4 or any of claims 5 to 8 as dependent on claim 4 wherein said winding is energised from a current source, and a gate-controlled semi-conductor switching device is arranged both to bypass current from said current source in response to a control signal applied to the gate of said device on de-energising said electromagnetic actuator, and to conduct the current which is discharged by said capacitor through said winding.
10. A residual current circuit breaker as claimed in claim 8 which comprises a transformer which is coupled to both conductors of said mains circuit and to circuit means arranged to generate a control signal which de-energises said electromagnetic actuator when the output of said transformer exceeds a predetermined value
11. A residual current circuit breaker as claimed in claim 10 wherein a winding of said electromagnetic actuator is connected in series with a gate-controlled semi-conductor switching device and a capacitor, said capacitor being charged when said winding is energised, and said circuit means is arranged to apply said control signal to the gate of said semi-conductor switching device to discharge said capacitor through said winding and through said semi-conductor switching device.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| GB8913633.7 | 1989-06-14 | ||
| GB898913633A GB8913633D0 (en) | 1989-06-14 | 1989-06-14 | Electromagnetic actuator arrangement |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA2018965A1 true CA2018965A1 (en) | 1990-12-14 |
Family
ID=10658400
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA 2018965 Abandoned CA2018965A1 (en) | 1989-06-14 | 1990-06-13 | Electromagnetic actuator arrangement |
Country Status (8)
| Country | Link |
|---|---|
| EP (1) | EP0403216B1 (en) |
| JP (1) | JPH0395905A (en) |
| AU (1) | AU624960B2 (en) |
| CA (1) | CA2018965A1 (en) |
| DE (1) | DE69011757T2 (en) |
| DK (1) | DK0403216T3 (en) |
| ES (1) | ES2057408T3 (en) |
| GB (1) | GB8913633D0 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AU673705B2 (en) * | 1993-01-29 | 1996-11-21 | H.P.M. Industries Pty Limited | Fault detection circuit breaker |
| ITUB20169940A1 (en) * | 2016-01-12 | 2017-07-12 | Antonio Ricciardiello | CIRCUIT INTERRUPTION DEVICE |
Family Cites Families (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE532028C (en) * | 1929-05-27 | 1931-08-25 | Siemens Schuckertwerke Akt Ges | Quick switch |
| US3280375A (en) * | 1963-01-17 | 1966-10-18 | Ite Circuit Breaker Ltd | Tripping device |
| US4063299A (en) * | 1975-10-24 | 1977-12-13 | Eagle Electric Mfg. Co. Inc. | Magnetically latched ground fault circuit interrupter |
| CH616271A5 (en) * | 1977-06-27 | 1980-03-14 | Weber Ag Fab Elektro | |
| JPS55127826A (en) * | 1979-03-26 | 1980-10-03 | Fuji Electric Co Ltd | Leakage breaker |
| US4442470A (en) * | 1982-09-10 | 1984-04-10 | Westinghouse Electric Corp. | Ground fault receptacle with arrangement for protecting internal electronics |
| FR2604294B1 (en) * | 1986-09-23 | 1994-05-20 | Merlin Et Gerin | MULTIPOLAR DIFFERENTIAL CIRCUIT BREAKER WITH MODULAR ASSEMBLY |
| US4739293A (en) * | 1987-02-19 | 1988-04-19 | Westinghouse Electric Corp. | Electromagnetic contactor with reduced noise magnetic armature |
| GB8710521D0 (en) * | 1987-05-02 | 1987-06-03 | Ashley Accessories Ltd | Residual current circuit breaker |
-
1989
- 1989-06-14 GB GB898913633A patent/GB8913633D0/en active Pending
-
1990
- 1990-06-12 EP EP19900306372 patent/EP0403216B1/en not_active Expired - Lifetime
- 1990-06-12 ES ES90306372T patent/ES2057408T3/en not_active Expired - Lifetime
- 1990-06-12 DK DK90306372T patent/DK0403216T3/en active
- 1990-06-12 DE DE1990611757 patent/DE69011757T2/en not_active Expired - Fee Related
- 1990-06-13 AU AU57001/90A patent/AU624960B2/en not_active Ceased
- 1990-06-13 CA CA 2018965 patent/CA2018965A1/en not_active Abandoned
- 1990-06-14 JP JP15413190A patent/JPH0395905A/en active Pending
Also Published As
| Publication number | Publication date |
|---|---|
| EP0403216A3 (en) | 1992-07-08 |
| ES2057408T3 (en) | 1994-10-16 |
| JPH0395905A (en) | 1991-04-22 |
| EP0403216B1 (en) | 1994-08-24 |
| DE69011757T2 (en) | 1995-04-27 |
| EP0403216A2 (en) | 1990-12-19 |
| AU5700190A (en) | 1990-12-20 |
| AU624960B2 (en) | 1992-06-25 |
| DK0403216T3 (en) | 1995-01-02 |
| GB8913633D0 (en) | 1989-08-02 |
| DE69011757D1 (en) | 1994-09-29 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| FZDE | Dead |