EP0671669B1 - Entwicklungseinheit für die Verwendung in einem elektrostatographischen Druckgerät - Google Patents

Entwicklungseinheit für die Verwendung in einem elektrostatographischen Druckgerät Download PDF

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Publication number
EP0671669B1
EP0671669B1 EP95301256A EP95301256A EP0671669B1 EP 0671669 B1 EP0671669 B1 EP 0671669B1 EP 95301256 A EP95301256 A EP 95301256A EP 95301256 A EP95301256 A EP 95301256A EP 0671669 B1 EP0671669 B1 EP 0671669B1
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EP
European Patent Office
Prior art keywords
developer
screw
developing
primary
developing unit
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
EP95301256A
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English (en)
French (fr)
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EP0671669A3 (de
EP0671669A2 (de
Inventor
Etienne Marie De Cock
Lucien Amedé De Schamphelaere
Bart Jozef Van Dessel
Daniel Louis Van Hoogten
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Xeikon NV
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Xeikon NV
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Publication date
Application filed by Xeikon NV filed Critical Xeikon NV
Priority to EP95301256A priority Critical patent/EP0671669B1/de
Publication of EP0671669A2 publication Critical patent/EP0671669A2/de
Publication of EP0671669A3 publication Critical patent/EP0671669A3/de
Application granted granted Critical
Publication of EP0671669B1 publication Critical patent/EP0671669B1/de
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • 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

Definitions

  • the present invention relates to a developing unit suited for developing an electrostatic latent image with dry pulverant two-component developer.
  • a dielectric recording member that may be a photoconductive dielectric recording member which after being uniformly charged is image-wise exposed to conductivity-increasing radiation producing thereby a "direct” or “reversal” toner-developable charge pattern on the recording member.
  • toner particles colouring particles
  • carrier particles magnetizable carrier particles
  • the electrostatic charge of the toner and carrier particles is obtained triboelectrically by agitation.
  • the charge sign of the toner particles is opposite to the charge sign of the carrier particles.
  • negatively charged toner is used.
  • toner-carrier mixture to the surface carrying the electrostatic charge image by means of a developing unit wherein toner and magnetizable carrier particles are mixed and a layer of the toner-carrier mixture, referred to herein as "developer” is picked up by an applicator such as a rotating sleeve or drum having magnets inside, forming a so-called magnetic brush on a "magnetic roller".
  • developer a layer of the toner-carrier mixture
  • the toner particles still adhering to the magnetically attracted carrier particles are brought into a developing zone wherein the toner particles are separated from the carrier particles by the electrostatic attraction forces of the electrostatic latent image to be developed and transfer to the latent electrostatic charge image.
  • a developing bias voltage of suitable polarity applied between the magnetic brush and the recording member to be developed decides whether the development is a "direct" or "reversed” development.
  • the magnetic brush from which toner particles are removed during each revolution, to be taken up by the developed electrostatic charge image, has to be supplied with fresh toner-carrier mixture. This is normally done by an agitator projecting or scooping up toner-carrier mixture onto the magnetic roller from a housing for holding the developer.
  • the partly exhausted developer is returned to the bulk of developer contained in the housing and has to be thoroughly mixed timely with freshly added toner to keep the toner-carrier weight ratio within acceptable limits for obtaining consistent development results.
  • the developing system proposed includes agitating means arranged between the secondary screw member means and the applicator, the agitating means including means for scooping up developer to fly onto the primary screw member to mix with developers supplied from a supply means.
  • the applicator comprises a rotatable developing sleeve having magnets located therein for attracting developer onto the sleeve.
  • the primary conveyance means is preferably adapted for conveying developer in the one direction substantially in parallel with the axis of rotation of the developing sleeve.
  • the housing has an extension protruding beyond one side of the developing zone, the extension comprising first and second channels into the first of which an end part of the primary conveyance means extends and into the second of which an end part of the secondary conveyance means extends.
  • the first and second channels may be substantially parallel to each other.
  • the channels may be interconnected by the passageway.
  • the supply means may open through an entrance opening into the first channel.
  • the developing unit may further comprise means to resist the flow of developer in the first channel, at a position downstream of the entrance opening, such as one or more magnets producing a static magnetic field penetrating into the first channel.
  • the primary and secondary conveyance means are preferably in the form of screws with an end portion of the secondary conveyance means extending beyond the passageway outside the width of the developing zone and the end portion has a screw thread reversed in direction with respect to screw thread direction of the remainder of the secondary conveyance means, thereby to convey developer into the passageway substantially without damming-up of developer at the secondary conveyance means end.
  • the first conveyance means is preferably screened from the agitator means to prevent the agitating means from projecting scooped-up developer onto the primary conveyance means.
  • the agitating means is a rotatable paddle wheel and means are provided for rotating said paddle wheel in the same sense as the rotation of the developing sleeve.
  • the developing sleeve may be associated with a doctor blade for determining the thickness of a developer layer formed on the sleeve in the developing zone.
  • the doctor blade preferably extends along the developing sleeve in a direction parallel to the axis thereof, and the blade is connected over its whole length to a plate following a part of the circumference of the sleeve.
  • the primary conveyance means is preferably located above the secondary conveyance means and the unit further comprises a first gutter positioned under the primary conveyance means and interposed between the primary conveyance means and secondary conveyance means.
  • the gutter may have a plurality of holes therethrough positioned along its length to allow portions of developer conveyed by the primary conveyance means to fall onto the secondary conveyance means.
  • the gutter may have a side wall the height of which decreases in the conveyance direction of the primary conveyance means, said side wall constituting a dam over which portions of developer conveyed by the primary conveyance means to fall onto the secondary conveyance means.
  • a second gutter may be positioned above the agitating means extending in a direction parallel to the axis of the developing sleeve, the second gutter having a plurality of holes therethrough positioned along its length to allow portions of developer removed from the developing sleeve by the doctor blade to fall back towards the agitating means.
  • the second gutter is preferably joined to the first gutter by a wall which serves to prevent scooped-up developer from being projected onto the primary conveyance means.
  • the supply means may comprise a hopper for fresh toner.
  • the unit may further comprise sensing means for sensing the concentration of toner in the developer in the passageway, the sensing means preferably comprising means for measuring the magnetic permeability of the developer in the passageway.
  • the supply means is sensitive to the output of the sensing means to dose toner to the housing in such a manner as to maintain the carrier / toner ratio of the developer within the housing at a substantially constant level.
  • the supply means may comprise a vessel capable of containing a larger volume of developer than the housing, the supply vessel being connected between the first and second channels to enable at least a portion of developer to be recycled through the vessel.
  • the Figures show a developing unit for use in an electrostatographic printer.
  • the developing unit shown by sectional view in the Figures 1 and 2 comprises a housing or casing 1.
  • the housing 1 has an opening 30 in its upper wall, the opening being directed towards a photoconductive drum 24 (partly shown in the drawing) which carries an electrostatic image to be developed on its surface 26.
  • the width of the opening 30 defines a developing zone Z (see Figure 1).
  • a rotary developing sleeve 2 having built-in magnets 3 (which in the embodiment shown in Figure 2 are stationary magnets) is located in the housing 1, adjacent the opening 30.
  • Agitating means in the form of a paddle wheel 4 is provided for agitating the bulk of the carrier-toner mixture inside the housing near developing sleeve 2.
  • the paddle wheel 4 has radially extending blades which are optionally inclined or curved for better scooping up developer onto the developing sleeve 2.
  • the housing 1 also contains a rotatable primary spiral screw 25 and a secondary spiral screw 28, separated by a gutter 7, the secondary spiral screw 28 being immersed in the bulk of carrier-toner mixture in the housing 1.
  • the spiral screws are formed of non-magnetic material, such as for example a plastics material or non-magnetic alloy.
  • the primary spiral screw 25 conveys carrier-toner mixture across the unit in one direction, parallel to the axis A of the developing sleeve 2 (indicated in Figure 1A) along the width of the developing zone Z away from the right hand end thereof as viewed in Figure 2. This developer is distributed through holes 6 arranged in the gutter 7 onto the secondary spiral screw 28.
  • the secondary spiral screw 28 is mounted substantially under the primary spiral screw 25, and in parallel therewith.
  • the secondary spiral screw 28 conveys the carrier-toner mixture received from the primary spiral screw 25, together with part of the bulk developer within the housing, across the unit in the opposite direction parallel to the axis A of the developing sleeve 2 along the width of the developing zone Z towards the right hand end thereof as viewed in Figure 2.
  • the right hand ends of the primary and secondary spiral screws 25 and 28 extend beyond the developing zone Z into an extension 10 (shown in dashed lines in Figure 2) of the housing, where they are located in first and second cavities or channels 11 and 12 respectively, the channels 11 and 12 taking the form of cylindrical holes.
  • a passageway 9 is located in the extension 10 of the housing 1 and communicates the two channels 11 and 12 for recycling carrier-toner mixture.
  • Channel 11 has an entrance opening 13 that serves to feed therethrough fresh toner for conveyance by the primary spiral screw 25.
  • the entrance opening is connected to a supply conduit of a hopper 20 containing fresh toner.
  • the primary spiral screw 25 is rotated in such a sense that the screw thread 5 thereof conveys the carrier-toner mixture in one direction substantially in parallel with the axis A of rotation of the developing sleeve 2.
  • the secondary spiral screw 28 is arranged substantially in parallel to the primary spiral screw 25 and is rotated in such a sense that the screw thread 8 thereof causes developer received through the holes 6 and developer coming from the paddle wheel along the developing sleeve 2 to be conveyed in a direction opposite to the conveyance direction of the primary spiral screw 25.
  • the secondary spiral screw is buried under developer powder present at the start of the development at the bottom of the housing 1.
  • toner-carrier mixture is pumped up into the passageway 9 and no damming up of toner-carrier mixture in the channel 12 can take place.
  • Figure 3 gives a partial front view illustrating the end part 28a of the secondary spiral screw 28 located in the channel 12. That part 28a of the secondary spiral screw 28 which extends beyond the passageway 9 has a screw thread 8a with a reversed spiralling sense with respect to the screw thread 8 of the remainder of the secondary spiral screw 28, as shown in the drawing.
  • the gutter 7 is joined to another gutter 14 that is in parallel position with respect to the developing sleeve 2 and extends above the paddle wheel 4.
  • the gutter 14 has a plurality of holes 15 therein, allowing any part of the developer not picked up by the developing sleeve 2 and/or removed therefrom by a doctor blade 16 to drop down towards the paddle wheel 4.
  • the gutter 14 joined to the gutter 7 by a separation wall 21, which serves to prevent scooped-up developer from being projected onto the primary spiral screw 25.
  • a doctor blade 16 determines the thickness of the developer layer on the developing sleeve 2 in the developing zone Z.
  • the doctor blade 16 extends in parallel position along the developing sleeve 2, and is connected over the whole of its length to a plate 17 following a part of the circumference of the sleeve 2.
  • the plate 17 serves for counter-acting toner dust circulation in the atmosphere of the housing 1 and prevents the escape of developer from the sleeve just beyond the doctor blade 16.
  • the developing unit has at least one stationary permanent magnet 18 (only one is shown in Figure 2) positioned adjacent the channel 11 at a position downstream of the entrance opening 13.
  • a flow resistance is built up for the magnetically susceptible carrier particles of the developer and consequently also for the toner particles that electrostatically cling thereto.
  • the flow resistance results in a better mixing of toner and carrier particles and into a more homogeneous developer.
  • the permanent magnet 18 located outside the channel 11 one may utilise a coil fed with direct current or even a permanent magnet located within the spiral screw 25 itself.
  • the passageway 9 between the secondary and the primary spiral screws is provided with a sensor 19 yielding signals determinative for the concentration of toner in the carrier-toner mass.
  • the sensor 19 may be a TC (toner concentration) sensor which measures the magnetic permeability of the carrier-toner mass in the passageway 9. After calibration, the magnetic permeability values can be translated into toner concentration values.
  • the signals obtained from the sensor may be used to control the feeding of fresh toner from hopper 20 into the developing unit.
  • the location of the sensor 19 in the passageway 9 is very convenient for an undisturbed measurement under circumstances wherein the packing density of the developer passing through the passageway 9 remains almost constant and is not influenced by moving elements inside the unit.
  • toner-carrier mixture is added through the entrance opening 13 and an overflow exit 22 opening from channel 12 allows recycling of the mixture through a supply vessel connected thereto.
  • the gutter 7 has a side wall 31 the height of which decreases in the conveyance direction of the primary spiral screw 25, the side wall 31 constituting a dam over which portions of developer conveyed by the primary spiral screw 25 fall onto the secondary spiral screw 28.
  • This construction has an advantage over the provision of holes in the gutter, as in the embodiment of Figures 1 to 3, since holes may become blocked or partially blocked in time, resulting in uneven distribution of the developer.
  • the gutter 7 is joined to another gutter 44 that is in parallel position with respect to the developing sleeve 2 and extends above the paddle wheel 4.
  • the gutter 44 is spaced from a plate 45, which is so positioned as to ensure that any part of the developer not picked up by the developing sleeve 2 and/or removed therefrom by a doctor blade 16 falls down towards the paddle wheel 4 on that side thereof which is towards the secondary spiral screw 28.

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

Claims (14)

  1. Entwicklungseinheit zur Verwendung in einem elektrostatografischen Drucker, umfassend:
    (i) ein Gehäuse (1) mit einer Öffnung (30), die eine Entwicklungszone (Z) definiert;
    (ii) eine Aufbringvorrichtung (2) zum Aufbringen von teilchenförmigem Träger/Toner-Entwickler durch die besagte Öffnung (30) in Richtung eines zu entwickelnden elektrostatografischen Bildes;
    (iii) eine Rühreinrichtung (4) zum Umrühren von Entwickler im Inneren des Gehäuses (1), zum Hochschaufeln von Entwickler aus dem Inneren des besagten Gehäuses (1) und zum Werfen von hochgeschaufeltem Entwickler in Richtung der besagten Aufbringvorrichtung (2);
    (iv) eine Zufuhreinrichtung (20) zum Zuführen von Toner in das besagte Gehäuse (1);
    (v) eine primäre Fördereinrichtung in Form einer primären Schnecke (25) zum Fördern von Entwickler aus der besagten Zufuhreinrichtung (20) in einer Richtung über die Breite der Entwicklungszone;
    (vi) eine sekundäre Fördereinrichtung in Form einer sekundären Schnecke (28) zum Aufnehmen des besagten Entwicklers aus der besagten primären Schnecke (25) über die Breite der Entwicklungszone und zum Fördern von Entwickler über die Breite der Entwicklungszone in einer zur Förderrichtung der besagten primären Schnecke (25) entgegengesetzten und im Wesentlichen parallelen Richtung, wobei die besagte primäre und sekundäre Schnecke (25, 28) jeweils einen jeweiligen Entwicklertransportpfad definieren, die durch einen Durchlass (9) außerhalb der Breite der Entwicklungszone (Z) miteinander verbunden sind, der das Zurückführen von Entwickler von der sekundären zur primären Schnecke (25) ermöglicht, dadurch gekennzeichnet, dass die besagte Zufuhreinrichtung außerhalb der Breite der Entwicklungszone (Z) angeordnet ist, dass sich ein Endteil (28a) der besagten sekundären Schnecke (28) außerhalb der Breite der besagten Entwicklungszone (Z) über den besagten Durchlass (9) hinaus erstreckt, und dass der besagte Endteil (28a) ein Schneckengewinde (8a) aufweist, dessen Richtung in Bezug zur Richtung des Schneckengewindes (8) der übrigen sekundären Schnecke (28) umgekehrt ist, um dadurch Entwickler im Wesentlichen ohne ein Aufstauen von Entwickler am Ende der besagten sekundären Schnecke (28) in den besagten Durchlass (9) zu fördern.
  2. Entwicklungseinheit nach Anspruch 1, bei welcher das besagte Gehäuse (1) einen über eine Seite der besagten Entwicklungszone (Z) hinausragenden Fortsatz (10) aufweist, wobei der besagte Fortsatz (10) einen ersten und zweiten Kanal (11, 12) umfasst, in deren ersten sich ein Endteil der besagten primären Schnecke (25) erstreckt, und in deren zweiten sich ein Endteil der besagten sekundären Schnecke (28) erstreckt, wobei sich die besagte Zufuhreinrichtung (20) durch eine Eintrittsöffnung (13) in den besagten ersten Kanal (11) öffnet.
  3. Entwicklungseinheit nach Anspruch 2, bei welcher die besagte Zufuhreinrichtung (20) einen Behälter umfasst, der ein größeres Entwicklervolumen als das besagte Gehäuse (1) aufnehmen kann, wobei der besagte Versorgungsbehälter zwischen den besagten ersten und zweiten Kanal (11, 12) geschaltet ist, um es zu ermöglichen, dass mindestens ein Teil des Entwicklers durch den besagten Behälter im Kreislauf geführt wird.
  4. Entwicklungseinheit nach Anspruch 2, weiter umfassend eine Einrichtung (18), um dem Entwicklerstrom in dem besagten ersten Kanal (11) an einer Stelle in Förderrichtung hinter der besagten Eintrittsöffnung (13) einen Widerstand entgegenzusetzen.
  5. Entwicklungseinheit nach Anspruch 4, bei welcher die besagte Einrichtung (18), um dem Entwicklerstrom einen Widerstand entgegenzusetzen, einen oder mehr Magnete umfasst, die ein statisches Magnetfeld erzeugen, das in den besagten ersten Kanal (11) eindringt.
  6. Entwicklungseinheit nach einem beliebigen vorangehenden Anspruch, bei welcher die besagte erste Schnecke (25) von der besagten Rühreinrichtung (4) abgeschirmt ist, um zu verhindern, dass die besagte Rühreinrichtung (4) hochgeschaufelten Entwickler auf die besagte primäre Schnecke (25) wirft.
  7. Entwicklungseinheit nach einem beliebigen vorangehenden Anspruch, bei welcher die besagte Aufbringvorrichtung eine Entwicklungshülse (2) ist, welche mit einem Abstreifmesser (16) zur Festlegung der Dicke einer in der Entwicklungszone (Z) auf der besagten Hülse gebildeten Entwicklerschicht verbunden ist, wobei sich das besagte Abstreifmesser (16) entlang der besagten Entwicklungshülse in einer zu ihrer Achse (A) parallelen Richtung erstreckt, und wobei das besagte Abstreifmesser (16) über seine gesamte Länge mit einer Platte (17) verbunden ist, die einem Teil des Umfangs der besagten Hülse folgt.
  8. Entwicklungseinheit nach einem beliebigen vorangehenden Anspruch, bei welcher in der besagten Betriebsausrichtung der Einheit die besagte primäre Schnecke (25) über der besagten sekundären Schnecke (28) angeordnet ist, und die besagte Einheit weiter eine erste Rinne (7) umfasst, die unter der besagten primären Schnecke (25) angeordnet und zwischen die besagte primäre Schnecke (25) und sekundäre Schnecke (28) eingesetzt ist, und die besagte erste Rinne (7) eine Mehrzahl von Öffnungen durch sie hindurch aufweist, die entlang ihrer Länge angeordnet sind, um es zu ermöglichen, dass von der besagten primären Schnecke (25) geförderte Entwicklerteile auf die besagte sekundäre Schnecke (28) fallen.
  9. Entwicklungseinheit nach einem beliebigen der Ansprüche 1 bis 7, bei welcher in der besagten Betriebsausrichtung der Einheit die besagte primäre Schnecke (25) über der besagten sekundären Schnecke (28) angeordnet ist, und die besagte Einheit weiter eine erste Rinne (7) umfasst, die unter der besagten primären Schnecke (25) angeordnet und zwischen die besagte primäre Schnecke (25) und sekundäre Schnecke (28) eingesetzt ist, und die besagte erste Rinne (7) eine Seitenwand (31) aufweist, deren Höhe in der Förderrichtung der primären Schnecke abnimmt, wobei die besagte Seitenwand (31) einen Damm bildet, über den von der besagten primären Schnecke (25) geförderte Entwicklerteile auf die besagte sekundäre Schnecke (28) fallen können.
  10. Entwicklungseinheit nach Anspruch 7, bei welcher eine zweite Rinne (14) über der besagten Rühreinrichtung angeordnet ist und sich in einer zur Achse (A) der besagten Entwicklungshülse parallelen Richtung erstreckt, wobei die besagte zweite Rinne (14) eine Mehrzahl von Öffnungen durch sie hindurch aufweist, die entlang ihrer Länge angeordnet sind, um es zu ermöglichen, dass durch das Abstreifmesser (16) von der Entwicklungshülse entfernte Entwicklerteile in Richtung der besagten Rühreinrichtung zurückfallen.
  11. Entwicklungseinheit nach Anspruch 8 oder 9, bei welcher eine zweite Rinne (14) über der besagten Rühreinrichtung angeordnet ist und sich in einer zur Achse (A) der besagten Entwicklungshülse parallelen Richtung erstreckt, wobei die besagte zweite Rinne (14) eine Mehrzahl von Öffnungen durch sie hindurch aufweist, die entlang ihrer Länge angeordnet sind, um es zu ermöglichen, dass durch das Abstreifmesser (16) von der Entwicklungshülse entfernte Entwicklerteile in Richtung der besagten Rühreinrichtung zurückfallen, wobei die besagte zweite Rinne (14) mit der besagten ersten Rinne (7) durch eine Wand (21) verbunden ist, die dazu dient, zu verhindern, dass hochgeschaufelter Entwickler auf die besagte primäre Schnecke (25) geworfen wird.
  12. Entwicklungseinheit nach einem beliebigen vorangehenden Anspruch, weiter umfassend eine Sensoreinrichtung zum Erfassen der Tonerkonzentration im Entwickler in dem besagten Durchlass (9).
  13. Entwicklungseinheit nach Anspruch 12, bei welcher die besagte Sensoreinrichtung eine Einrichtung zum Messen der magnetischen Permeabilität des Entwicklers in dem besagten Durchlass (9) umfasst.
  14. Entwicklungseinheit nach Anspruch 13, bei welcher die besagte Zufuhreinrichtung (20) auf die Ausgangsgröße der besagten Sensoreinrichtung anspricht, um Toner in einer solchen Weise in das besagte Gehäuse (1) zu dosieren, dass das Träger/Toner-Verhältnis des Entwicklers innerhalb des Gehäuses (1) auf einem im Wesentlichen konstanten Niveau gehalten wird.
EP95301256A 1994-03-11 1995-02-27 Entwicklungseinheit für die Verwendung in einem elektrostatographischen Druckgerät Expired - Lifetime EP0671669B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
EP95301256A EP0671669B1 (de) 1994-03-11 1995-02-27 Entwicklungseinheit für die Verwendung in einem elektrostatographischen Druckgerät

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
EP94301784 1994-03-11
EP94301784 1994-03-11
EP95301256A EP0671669B1 (de) 1994-03-11 1995-02-27 Entwicklungseinheit für die Verwendung in einem elektrostatographischen Druckgerät

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EP0671669A2 EP0671669A2 (de) 1995-09-13
EP0671669A3 EP0671669A3 (de) 1996-04-24
EP0671669B1 true EP0671669B1 (de) 1998-04-15

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL2016148B1 (en) * 2016-01-25 2017-07-31 Xeikon Mfg Nv Developing unit with improved conveying assembly.

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0352102A2 (de) * 1988-07-22 1990-01-24 Canon Kabushiki Kaisha Bildaufzeichnungsgerät

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS58163968A (ja) * 1982-03-24 1983-09-28 Konishiroku Photo Ind Co Ltd 現像装置
JPS6273284A (ja) * 1985-09-27 1987-04-03 Fuji Xerox Co Ltd 複写機の磁気ブラシ現像装置
JPH0648407B2 (ja) * 1986-06-09 1994-06-22 キヤノン株式会社 現像装置
JPH05127537A (ja) * 1991-11-08 1993-05-25 Fujitsu Ltd 現像装置
JPH05313488A (ja) * 1992-05-08 1993-11-26 Ricoh Co Ltd 現像装置

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0352102A2 (de) * 1988-07-22 1990-01-24 Canon Kabushiki Kaisha Bildaufzeichnungsgerät

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EP0671669A3 (de) 1996-04-24
EP0671669A2 (de) 1995-09-13

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