EP0628889B1 - Mélangeur de toner pour appareil de développement à brosse magnétique - Google Patents

Mélangeur de toner pour appareil de développement à brosse magnétique Download PDF

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Publication number
EP0628889B1
EP0628889B1 EP94113291A EP94113291A EP0628889B1 EP 0628889 B1 EP0628889 B1 EP 0628889B1 EP 94113291 A EP94113291 A EP 94113291A EP 94113291 A EP94113291 A EP 94113291A EP 0628889 B1 EP0628889 B1 EP 0628889B1
Authority
EP
European Patent Office
Prior art keywords
magnetic brush
developer material
housing
replenishment
sump
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.)
Expired - Lifetime
Application number
EP94113291A
Other languages
German (de)
English (en)
Other versions
EP0628889A1 (fr
Inventor
Larry W. Peer
Susan P. Westbrook
Christopher J. Olan
Richard A. Weitzel
Timothy G. C/O Eastman Kodak Co. Armstrong
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.)
Eastman Kodak Co
Original Assignee
Eastman Kodak Co
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
Priority claimed from US07/444,256 external-priority patent/US5045886A/en
Priority claimed from US07/444,209 external-priority patent/US4999675A/en
Priority claimed from US07/444,257 external-priority patent/US5005516A/en
Priority claimed from US07/444,210 external-priority patent/US5041875A/en
Application filed by Eastman Kodak Co filed Critical Eastman Kodak Co
Publication of EP0628889A1 publication Critical patent/EP0628889A1/fr
Application granted granted Critical
Publication of EP0628889B1 publication Critical patent/EP0628889B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/0896—Arrangements or disposition of the complete developer unit or parts thereof not provided for by groups G03G15/08 - G03G15/0894
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/0822—Arrangements for preparing, mixing, supplying or dispensing developer
    • G03G15/0877—Arrangements for metering and dispensing developer from a developer cartridge into the development unit
    • G—PHYSICS
    • G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
    • G03G—ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY
    • G03G15/00—Apparatus for electrographic processes using a charge pattern
    • G03G15/06—Apparatus for electrographic processes using a charge pattern for developing
    • G03G15/08—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer
    • G03G15/09—Apparatus for electrographic processes using a charge pattern for developing using a solid developer, e.g. powder developer using magnetic brush

Definitions

  • the invention relates in general to electrostatographic reproduction apparatus, and more particularly to an improved magnetic brush development apparatus for an electrostatographic reproduction apparatus.
  • Magnetic brush development apparatus for applying developer material to a latent image in an electrostatographic reproduction apparatus are well known in the art.
  • Such apparatus may include a housing having a sump portion which contains a supply of developer material.
  • the developer material comprises a mixture of magnetic carrier particles and smaller pigmented marking particles
  • the material in the sump is agitated to triboelectrically charge the material prior to delivering it to a magnetic brush where it can be brought into association with, and transferred to, an electrostatic latent image to develop such image.
  • U.S.-A-4,671,207 discloses a magnetic brush development apparatus particularly suitable for use with developer material having pigmented marking particles and permanent magnetic carrier particles. More particularly, the disclosed apparatus include a ribbon blender that is used for agitating (mixing), feeding and triboelectrically charging such material in the sump portion of a magnetic brush development apparatus, and a feed mechanism that delivers material from the sump portion to a magnetic brush. The material delivered to the magnetic brush is applied to the latent electrostatic image in a development zone to develop the image.
  • the ribbon blender is constructed to provide uniform flow distribution of developer material across the length of the apparatus so that a sufficient supply of material is delivered to the magnetic brush over its full extent to uniformly develop the entire latent electrostatic image.
  • a take-off skive in contact with the magnetic brush downstream of the development zone, strips excess developer material from the magnetic brush and returns such material to the sump portion.
  • Typical replenishment devices include a reservoir for replenishment material with a flow communication path between the reservoir and the sump of the of the development apparatus.
  • a selectively actuable member such as a roller, controls flow of replenishment material through the path. It has been found that under certain conditions the set up latitude between the replenishment roller and the flow communication path is unduly limited which can result in inconsistent replenishment or marking particle level sensor inconsistencies. Further, under certain conditions measurement of level of replenishment material in the reservoir is inconsistent, which can result in running out of replenishment material without knowing it.
  • particulate material in an uncharged, or low charged state becomes airborne.
  • airborne material can cause undesirable artifacts in the developed images and/or exit from the development apparatus to contaminate the interior of the electrostatographic reproduction machine.
  • the development apparatus includes a housing having a portion defining a sump adapted to contain a supply of developer material, and a magnetic brush located substantially within the housing in spaced relation to the sump portion for applying developer material to the latent image.
  • a feed mechanism including a metering assembly located within the housing between the sump portion and the magnetic brush transports developer material from the sump to the magnetic brush, and a mechanism located in the sump portion agitates developer material and transports developer material to the feed mechanism.
  • a take-off skive for stripping development material from the magnetic brush after application to a latent image and directing such material to the sump portion is mounted so that the skive is self-adjustably supported between the metering assembly and the magnetic brush.
  • flow of developer material is directed from the wall of the housing adjacent to the sump portion back into the agitating and transport mechanism.
  • developer material in the sump portion is replenished by a device which includes a reservoir for replenishment material adjacent to the sump portion, a flow communication path between the reservoir and the sump portion and a selectively rotatable roller located relative to the path to control flow of replenishment material through the path.
  • the entrance to the path is configured to engage the roller such that the set up latitude between the roller and path is increased. Measuring the level of replenishment material in the reservoir is facilitated by the material monitor located in the bottom of the reservoir immediately upstream of the flow communication path, the surface of the monitor being periodically swept to assure accurate measurement of replenishment material level. Still further, a shield is located upstream of the development zone between the housing and the image carrying member for containing developer material within the development zone to substantially prevent escape of airborne particulate material from the apparatus.
  • Fig. 1 shows an improved magnetic brush development apparatus according to this invention, generally designated by the numeral 10.
  • the apparatus 10 is adapted to provide a supply of developer material, including pigmented marking particles and carrier particles, to an electrostatic latent image carried by a member 12 in order to develop the latent image on the member with the marking particles.
  • the member 12 which is for example part of an electrostatographic reproduction apparatus, is in the form of an endless web or a drum, or can be discrete sheets on which a reproduction is formed.
  • the member 12 is moved past apparatus 10 in the direction shown by the arrow A during development of the latent image on the member.
  • Apparatus 10 comprises a housing 14 having spaced, generally parallel, substantially vertical side walls 16, 18; a generally semi-cylindrical bottom wall 20 that joins the side walls; and end walls (not shown).
  • the lower portion of the housing defines a sump S for containing a supply of developer material.
  • the developer material can be of any known type, for example including two-component developer material comprising hard, permanent magnetic carrier particles and pigmented marking particles, such as disclosed in U.S.-A-4,546,060.
  • Developer material in sump S is agitated in order to mix the marking particles and carrier particles, provide triboelectric charging of the developer material, move the material along the length of the sump, and deliver developer material to a feed mechanism 60.
  • agitation is effected by a ribbon blender generally designated by the numeral 26, such as disclosed in the aforementioned U.S.-A- 4,671,207.
  • the ribbon blender 26 comprises an outer helical ribbon 28 and an inner helical ribbon 30. Both ribbons are coiled concentrically about a shaft 32.
  • Shaft 32 is, in turn, concentrically located with respect to the semi-cylindrical bottom wall 20 of the housing 14, and runs for substantially the full length thereof.
  • the ribbons 28, 30 rotate with the shaft 32.
  • Ribbon 28 may have the same pitch throughout its length, or may have one pitch over half its length and the opposite pitch over the other half of its length.
  • the pitch orientation of ribbon 30 is selected to be opposite to the pitch orientation of ribbon 28.
  • the marking particles may not adequately mix with the carrier particles before delivery to the feed mechanism 60.
  • marking particles may be left uncharged or may only be charged to a low level insufficient to function in the desired manner during development of the latent electrostatic image on the member 12. This may result in formation of airborne marking particles which can escape from the development station, and artifacts in a finished reproduction due to incomplete development.
  • a protuberance 16a is formed on the wall 16 of the development station housing 14 adjacent to the ribbon blender 26 upstream of the feed mechanism 60.
  • the protuberance 16a which runs substantially the full length of the housing 14, directs flow of developer material (particularly any replenished marking particles) from the wall of the housing adjacent to the sump portion back into the ribbon blender thereby creating turbulence in the developer material being agitated by the ribbon blender to effectively extend the mixing path for the material.
  • a magnetic brush is located at the top of housing 14.
  • the magnetic brush 36 may be of any suitable construction, such as illustrated for example in Fig. 1, where the magnetic brush includes a shell 38 of a non-magnetic material that rotates counterclockwise as indicated by arrow 40 about a core 42.
  • Core 42 comprises a plurality of permanent magnets rotatable in a clockwise direction as shown by arrow 46.
  • the axis of rotation of the core coincident with the axis of rotation of the shell, is designated generally by the numeral 48.
  • a portion of the magnetic brush 36 projects through the top of the housing 14 and lies directly underneath the electrostatic latent image carrying member 12.
  • the feed mechanism 60 includes a metering assembly 50 having a plate defining an elongated feed slot 54 that extends substantially the full length of the magnetic brush and lies adjacent to the outer surface of the magnetic brush shell 38. Developer material received from the lower portion of the housing 14 passes through slot 54 to the brush 36, such material being attracted to the outer surface of shell 38 by the magnets in the core 42 of the magnetic brush.
  • a transport assembly 60a for the feed mechanism 60 is located between metering assembly 50 and the ribbon blender 26. The transport assembly 60a receives developer material from the sump S and the ribbon blender 26, and transports such material to the metering assembly 50 and through the slot 54 to the magnetic brush 36.
  • the transport assembly 60a comprises, for example, a shell rotatable in a counterclockwise direction shown by the arrow with a plurality of stationary magnets that extend counterclockwise from a position generally directly above the ribbon blender 26 to a position just ahead of the feed slot 54 (approximately 160 degrees). Developer material from the sump is attracted to the shell and held to the shell in the area under the influence of the magnets. Thus the material can be transported from the sump to the slot 54 without dropping from the shell.
  • developer material provided to the magnetic brush 36 is carried by the shell 38 into operative contact with the latent image carrying member 12 for developing an electrostatic latent image on the image bearing member with pigmented marking particles in a development zone between the brush and the member.
  • some percentage of the marking particles are not charged (or have low charge) and become airborne. As noted, these particles can cause image artifacts or may exit the development apparatus 10 to cause contamination within the reproduction apparatus or its environment.
  • a contamination control flap 44 is provided in order to substantially prevent escape of the airborne marking particles from the development apparatus 10.
  • the flap 44 is a thin flexible member fixed to the housing 14 upstream of the development zone.
  • connection of the flap 44 to the housing 14 is effected such that the flap extends into the path of the latent image carrying member 12, and is oriented at an angle with respect to the member to effect engagement of the flap with the member under a minimal engagement force. In this manner damage to the member 12 or undue wear of the flap 44 is minimized.
  • the flap 44 then serves as a seal between the development apparatus 10 and the member 12. Accordingly, any airborne marking particles are trapped and forced into the developer nap of the development zone. In such zone, the marking particles are charged and become part of the developed image, or are returned with the excess developer material exiting the development zone. In this manner, escape of the airborne marking particles is substantially prevented and build up of uncharged marking particle within the development apparatus 10 is greatly reduced.
  • the take-off skive 74 includes an elongated blade 76 for removing developer material passing through the development zone, from the shell 38.
  • the blade 76 is attached to mounting members 78 (one shown in the drawings). As best shown in Figs.
  • the mounting members 78 define slots 78a which are adapted to receive pins 80 respectively extending from end blocks 82 supporting the magnetic brush 36 whereby the take-off skive is capable of limited self-adjusting movement.
  • the slots 78a are oriented so that the limited movement of the take-off skive 74, for any particular development apparatus, automatically defines a position for the skive determined by the plate of the metering assembly 50 (engaged by the members 78) and the contour of the shell 38 (engaged by the blade 76).
  • the blade 76 is held in contact with the shell 38 by developer material scraped off of the shell. That is, the field of the magnets of the core 42 act to attract the developer material on the blade pulling the blade into intimate contact with the shell.
  • the lower torque is established for the magnetic brush 36 than with prior take-off skive mounting arrangements employing positive forces for blade/ shell engagement.
  • the lower torque is particularly significant in that it serves several purposes. It reduces heat generated by the development apparatus, wear to the blade of the skive, and the amount of flakes produced between the blade and the shell.
  • a replenishment system 70 is located at one side of the housing 14 adjacent to the side wall 18.
  • the replenishment system 70 includes a reservoir 72 for storing a supply of marking particle replenishment material.
  • the common wall 18 defines an opening 18a which provides a flow communication path between the marking particle reservoir 72 and the sump S.
  • a fibrous reple- nishment brush 90 is rotatably mounted in the bottom of the reservoir 72 adjacent to the opening 18a, the fibers of the brush extending through the opening.
  • the replenishment brush 90 when not rotating acts to seal the opening to prevent marking particles from flowing from the reservoir to the sump. However, when the concentration of marking particles in the developer material in the sump (as determined by any well known concentration monitor for example shown in Fig. 1 as mechanism 92) falls below a desired level for adequate latent image development, the replenishment brush 90 is selectively rotated to feed a quantity of fresh marking particles from the reservoir to the sump.
  • the portion of the wall 18 forming the marginal edge 18b of the opening 18a has a saw-toothed configuration (see Fig. 2). When the brush 90 is rotated in a counterclockwise direction, the saw-toothed configuration acts to readily comb marking particles out of the fibers of the replenishment brush.
  • the saw-toothed configuration When compared to straight walls found in replenishment systems of prior development apparatus, the saw-toothed configuration reduces the area in heavy contact with the the brush fiber, concomitantly reducing the torque required to rotate the replenishment brush. As a result of this torque reduction, the tolerance for locating the replenishment brush 90 relative to the opening 18a is significantly expanded. This, in turn, broadens the set up latitude for the replenishment brush under which acceptable replenishment rates can be accomplished without producing unacceptably high torque levels.
  • the replenishment system 70 also includes an improved mechanism for sensing the level of marking particles in the reservoir 72.
  • the level sensing mechanism includes a sensor 94 mounted at the bottom of the replenishment system housing in a substantially horizontal orientation. Such orientation is necessary to properly provide an "out of marking particles" signal where the marking particles are fed from the reservoir near one side at the bottom as shown in Fig. 1 of the drawings.
  • a wiper 96 is attached to the the outboard end of a rotatable marking particle agitator 98 within the reservoir. The length of the agitator 98 and the size of the wiper 96 are selected such that the wiper sweeps marking particles from the face of the sensor 94 toward the replenishment brush 90 as the agitator is rotated in a counterclockwise direction.
  • the marking particles As the agitator 98 passes the sensor 94, the marking particles back fill behind the wiper 96 to recover the sensor. When there is not enough marking particles to fill in after passage of the agitator, the sensor will detect that the "out of marking particles" condition exists and produce the appropriate warning signal. In this manner, marking particle level sensing is consistently assured.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Dry Development In Electrophotography (AREA)
  • Magnetic Brush Developing In Electrophotography (AREA)

Claims (2)

  1. Appareil de développement à brosse magnétique destiné à appliquer un matériau développateur à une image latente sur un élément mobile (12) porteur d'image, ledit appareil comprenant :
    un boîtier (14) comportant une partie de paroi (20) définissant un carter (S) adapté pour contenir une réserve de matériau de développateur,
    une brosse magnétique (36) située à l'intérieur dudit boîtier destinée à appliquer du matériau développateur à l'image latente,
    un mécanisme d'alimentation (26, 60) comprenant un ensemble de mesure (50) situé à l'intérieur dudit boîtier entre ladite partie de carter et ladite brosse magnétique (36),
    une lame de grattage (74) destinée à enlever du matériau développateur de ladite brosse magnétique (36) après application à une image latente, et à orienter un tel matériau vers ladite partie de carter,
    un moyen (16a) destiné à orienter un flux de matériau développateur jusque dans des moyens d'agitation (26) et de transport (60) dudit mécanisme d'alimentation,
    un moyen (44) situé en amont de la zone de développement, destiné à former un écran entre ledit boîtier et ledit élément porteur d'image (12) afin d'empêcher l'échappement hors de l'appareil d'un matériau de particules en suspension dans l'air,
    un dispositif de renouvellement de matériau développateur (70) comprenant un réservoir (72) destiné au renouvellement du matériau, contigu à ladite partie de carter,
    un trajet de communication de flux entre ledit réservoir et ladite partie de carter, un moyen étant situé dans un tel trajet de façon à réguler le flux du matériau de renouvellement, et
    un moyen destiné à mesurer le niveau du matériau de renouvellement dans ledit réservoir (72), dans lequel
    ledit moyen d'orientation de flux (16a) comprend une protubérance fixée à la paroi interne dudit boîtier, saillant vers ledit moyen d'agitation afin d'améliorer le mélange du matériau développateur.
  2. Appareil de développement à brosse magnétique selon la revendication 1, caractérisé en ce que ledit moyen d'orientation de flux (16a) est situé en amont dudit moyen de transport (60).
EP94113291A 1989-12-01 1990-11-26 Mélangeur de toner pour appareil de développement à brosse magnétique Expired - Lifetime EP0628889B1 (fr)

Applications Claiming Priority (11)

Application Number Priority Date Filing Date Title
US444256 1982-11-23
US44425889A 1989-12-01 1989-12-01
US444258 1989-12-01
US07/444,256 US5045886A (en) 1989-12-01 1989-12-01 Device for improving mixing in a magnetic brush development apparatus
US07/444,209 US4999675A (en) 1989-12-01 1989-12-01 Magnetic brush development apparatus including a self-adjustable take-off skive
US07/444,257 US5005516A (en) 1989-12-01 1989-12-01 Device for aiding in measuring pigmented marking particle level in a magnetic brush development apparatus
US444257 1989-12-01
US444209 1989-12-01
US07/444,210 US5041875A (en) 1989-12-01 1989-12-01 Developer replenishment device with increased set up latitude
US444210 1989-12-01
EP91900454A EP0456800B1 (fr) 1989-12-01 1990-11-26 Appareil de developpement a brosse magnetique

Related Parent Applications (1)

Application Number Title Priority Date Filing Date
EP91900454.9 Division 1990-11-26

Publications (2)

Publication Number Publication Date
EP0628889A1 EP0628889A1 (fr) 1994-12-14
EP0628889B1 true EP0628889B1 (fr) 1997-03-12

Family

ID=27541621

Family Applications (4)

Application Number Title Priority Date Filing Date
EP94113291A Expired - Lifetime EP0628889B1 (fr) 1989-12-01 1990-11-26 Mélangeur de toner pour appareil de développement à brosse magnétique
EP94113292A Withdrawn EP0628890A1 (fr) 1989-12-01 1990-11-26 Appareil de développement à brosse magnétique
EP91900454A Expired - Lifetime EP0456800B1 (fr) 1989-12-01 1990-11-26 Appareil de developpement a brosse magnetique
EP19940113290 Expired - Lifetime EP0628892B1 (fr) 1989-12-01 1990-11-26 Appareil de développement à brosse magnétique avec lame de raclage

Family Applications After (3)

Application Number Title Priority Date Filing Date
EP94113292A Withdrawn EP0628890A1 (fr) 1989-12-01 1990-11-26 Appareil de développement à brosse magnétique
EP91900454A Expired - Lifetime EP0456800B1 (fr) 1989-12-01 1990-11-26 Appareil de developpement a brosse magnetique
EP19940113290 Expired - Lifetime EP0628892B1 (fr) 1989-12-01 1990-11-26 Appareil de développement à brosse magnétique avec lame de raclage

Country Status (4)

Country Link
EP (4) EP0628889B1 (fr)
JP (1) JP2989006B2 (fr)
DE (3) DE69030203T2 (fr)
WO (1) WO1991008523A1 (fr)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05313488A (ja) * 1992-05-08 1993-11-26 Ricoh Co Ltd 現像装置
JP5983025B2 (ja) * 2012-05-22 2016-08-31 富士ゼロックス株式会社 現像装置及び画像形成装置

Family Cites Families (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3669072A (en) * 1970-02-11 1972-06-13 Xerox Corp Developer apparatus
JPS584164A (ja) * 1981-07-01 1983-01-11 Konishiroku Photo Ind Co Ltd 現像装置
JPS57115576A (en) * 1981-07-27 1982-07-19 Canon Inc Developer
JPS59189379A (ja) * 1983-04-13 1984-10-26 Fuji Xerox Co Ltd 現像装置
JPS6067978A (ja) * 1983-09-22 1985-04-18 Ricoh Co Ltd 現像装置
JPS60247667A (ja) * 1984-05-24 1985-12-07 Fuji Xerox Co Ltd 複写機のトナ−供給装置
US4671207A (en) * 1985-12-11 1987-06-09 Eastman Kodak Company Magnetic brush development apparatus
JPH083678B2 (ja) * 1986-08-11 1996-01-17 株式会社東芝 現像装置
JPS63108369A (ja) * 1986-10-24 1988-05-13 Canon Inc 乾式現像装置
US4707107A (en) * 1986-11-28 1987-11-17 Eastman Kodak Company Electrophotographic development apparatus with an improved ribbon blender
US4748471A (en) * 1987-07-06 1988-05-31 Eastman Kodak Company Development apparatus having means for rapidly shutting off the flow of developer to a magnetic brush
US4797704A (en) * 1987-11-03 1989-01-10 Eastman Kodak Company Disposable development station having means for assisting in the feeding of the toner supply and preventing replenishment of the toner supply

Also Published As

Publication number Publication date
EP0628892A1 (fr) 1994-12-14
DE69029749T2 (de) 1997-07-31
EP0456800B1 (fr) 1995-07-19
DE69030203D1 (de) 1997-04-17
JP2989006B2 (ja) 1999-12-13
JPH04503268A (ja) 1992-06-11
EP0628892B1 (fr) 1997-01-15
DE69029749D1 (de) 1997-02-27
WO1991008523A1 (fr) 1991-06-13
DE69030203T2 (de) 1997-10-02
EP0628890A1 (fr) 1994-12-14
EP0628889A1 (fr) 1994-12-14
DE69021045D1 (de) 1995-08-24
DE69021045T2 (de) 1996-03-21
EP0456800A1 (fr) 1991-11-21

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