EP0439145B1 - Auflade-Element mit einer Elektrodenstruktur und dieses verwendende Aufladevorrichtung in einer abnehmbaren Arbeitseinheit für ein Bilderzeugungsgerät - Google Patents

Auflade-Element mit einer Elektrodenstruktur und dieses verwendende Aufladevorrichtung in einer abnehmbaren Arbeitseinheit für ein Bilderzeugungsgerät Download PDF

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Publication number
EP0439145B1
EP0439145B1 EP19910100831 EP91100831A EP0439145B1 EP 0439145 B1 EP0439145 B1 EP 0439145B1 EP 19910100831 EP19910100831 EP 19910100831 EP 91100831 A EP91100831 A EP 91100831A EP 0439145 B1 EP0439145 B1 EP 0439145B1
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EP
European Patent Office
Prior art keywords
charging
blade
supporting
supporting member
blade member
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
EP19910100831
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English (en)
French (fr)
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EP0439145A3 (en
EP0439145A2 (de
Inventor
Hiroyuki C/O Canon Kabushiki Kaisha Adachi
Norihisa C/O Canon Kabushiki Kaisha Hoshika
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Canon Inc
Original Assignee
Canon Inc
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Filing date
Publication date
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Publication of EP0439145A2 publication Critical patent/EP0439145A2/de
Publication of EP0439145A3 publication Critical patent/EP0439145A3/en
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Publication of EP0439145B1 publication Critical patent/EP0439145B1/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
    • G03G15/02—Apparatus for electrographic processes using a charge pattern for laying down a uniform charge, e.g. for sensitising; Corona discharge devices
    • G03G15/0208—Apparatus for electrographic processes using a charge pattern for laying down a uniform charge, e.g. for sensitising; Corona discharge devices by contact, friction or induction, e.g. liquid charging apparatus
    • G03G15/0216—Apparatus for electrographic processes using a charge pattern for laying down a uniform charge, e.g. for sensitising; Corona discharge devices by contact, friction or induction, e.g. liquid charging apparatus by bringing a charging member into contact with the member to be charged, e.g. roller, brush chargers
    • G03G15/0233—Structure, details of the charging member, e.g. chemical composition, surface properties

Definitions

  • This invention relates to a charging member for charging a member to be charged, an image forming apparatus, such as an electrophotographic apparatus or the like, having the charging member, and a process unit detachable relative to the apparatus.
  • a corona discharger such as a corotron, a scorotron or the like, having a wire electrode and a shield electrode surrounding the wire electrode and having an excellent charging uniformness has been widely used as a means for uniformly charging the surface of an image carrying member, such as a photosensitive member, a dielectric member or the like, serving as a member to be charged in an image forming apparatus, such as an electrophotographic copier, an electrophotographic printer, a recording apparatus or the like.
  • the corona discharger has the following problems: an expensive high-voltage power supply is needed. Space is needed for the charger itself, as shield space for the high-voltage power supply, and the like. A large amount of corona products, such as ozone and the like, are produced, and hence additional means and mechanisms are needed in order to deal with the corona products. These factors result in a large and expensive apparatus.
  • contact charging by contacting a contact charging member, to which a voltage (for example, a DC voltage of about 1 - 2 kV (kilovolts), or a superposed voltage composed of a DC voltage and an AC voltage) is applied from a power supply, to the surface of an image carrying member, serving as a member to be charged, the surface of the image carrying member is charged at a predetermined potential.
  • a voltage for example, a DC voltage of about 1 - 2 kV (kilovolts), or a superposed voltage composed of a DC voltage and an AC voltage
  • the blade charging method is particularly effective for a small image forming apparatus because it provides for an inexpensive and compact apparatus.
  • One of the problems associated with the contact charging methods including the blade charging method is as follows: if a pinhole portion (a surface defect portion in a member to be charged) is present in an image carrying member, such as a photosensitive member or the like, a spark discharge is apt to occur between a contact charging member, to which a voltage is applied, in contact with the surface of the image carrying member in order to charge the suface of the image carrying member and the pinhole portion in the image carrying member.
  • FIGS. 6(A) and 6(B) illustrate a model for explaining the charge leak phenomenon.
  • a photosensitive member 1 serves as an image carrying member (a member to be charged) whose surface moves in the direction of the arrow. Pinhole portions P are present in the photosensitive member 1.
  • a blade member 2 (hereinafter termed a "charging blade") of a contact charging member to which a voltage is applied is in contact with the surface of the photosensitive member 1 in order to charge the surface.
  • FIG. 6(B) is an equivalent circuit of FIG. 6(A).
  • the pinhole portions P in the photosensitive member 1 have lower resistance values than other portions. Hence, when the charging blade 2 contacts the pinhole portions P or the surface of the charging blade 2 comes close to the pinhole portions P, spark discharges S are apt to occur between the charging blade 2 and the pinhole portions P. When the discharges S occur, potentials V A , V B , --- V z at respective portions applied on the surface of the photosensitive member 1 in the direction of the longitudinal direction of the photosensitive member 1 (the direction of the generatrix of the photosensitive member 1) become almost 0 V (volt). As a result, electric charges cannot be held on the surface of the photosensitive member 1 over the entire surface of the contact charging region including the pinhole portions P in contact with the charging blade 2.
  • the pinholes P are apt to be produced, for example, during the production of an image carrying member (a member to be charged), such as a photosensitive member or the like, due to scratching, or due to dielectric breakdown. It is rather difficult to completely eliminate pinholes.
  • the distance (the free length of the blade) between the distal end of a rigid blade supporting member made, for example, of sheet metal and a portion of the charging blade 2 in contact with the member to be charged must be considerably larger than the thickness of the charging blade 2. Accordingly, when a voltage is applied from the blade supporting member to the charging blade 2, the voltage drop in the charging blade 2 becomes large, causing a decrease in the potential of the portion of the charging blade 2 in contact with the member to be charged. Hence, it is necessary to attach a back electrode to the charging blade 2, but there has been no excellent means for producing a charging blade having a back electrode.
  • document EP-A-0 308 185 see preamble of claims 1, 7, 14 and 20 discloses a charging device wherein a charging member is constituted of a resistive blade member being in contact with a member to be charged and a conductive member arranged between the blade member and a supporting member.
  • the present invention has been made in consideration of the above-described problems.
  • the present invention pertains to a charging member as defined in claim 1, a process unit as defined in claim 7, an electrophotographic image forming apparatus as defined in claim 14, and a method for making a charging member as defined in claim 20.
  • FIG. 2 is a schematic diagram of the configuration of a principal part of an image forming apparatus which incorporates a contact charging means using a contact charging member according to the present invention as the charging processing means for an image carrying member.
  • a rotating-drum-type electrophotographic photosensitive member (termed hereinafter a "photosensitive drum”) serves as an image carrying member.
  • the photosensitive drum 1 is composed of an organic photoconductive layer la which is a surface layer, and a grounded conductive substrate 1b made, for example, of aluminum for supporting the organic photoconductive layer 1a.
  • the photosensitive drum 1 is rotatably driven in the clockwise direction as shown by arrow A at a predetermined circumferential speed (process speed).
  • the photosensitive drum 1 is uniformly charged at a predetermined polarity and a predetermined potential during its rotation by a charging blade 2 serving as a contact charging member of a contact charging device (to be described later).
  • the charged surface of the photosensitive drum 1 is subjected to exposure L (for example, exposure by an analog optical system for imaging and exposing the image of an original, scanning exposure by a digital optical system including a laser-beam scanner, an LED array or the like) in accordance with object image information at an exposing portion.
  • exposure L for example, exposure by an analog optical system for imaging and exposing the image of an original, scanning exposure by a digital optical system including a laser-beam scanner, an LED array or the like
  • the formed latent image is then subjected to normal or reversal development using toner by a developing unit 7.
  • a transfer material Pa is fed from a paper feed mechanism (not shown), and is supplied to a space (transfer portion) between the photosensitive drum 1 and a transfer roller 8 (for example, a corona charger may also be used), serving as transfer means, with a predetermined timing by registration rollers 10.
  • the developed image formed on the photosensitive drum 1 is sequentially transferred to the fed transfer material Pa.
  • the transfer material Pa passing through the transfer portion is separated from the surface of the photosensitive drum 1, and is guided into a fixing unit (not shown) by feed means 11.
  • the image on the transfer material Pa is fixed in the fixing unit.
  • Unnecessary particles remaining on the surface of the photosensitive drum 1 after image transfer are removed by a cleaning unit 9, and the photosensitive drum 1 is repeatedly used for forming images.
  • the image forming apparatus of the present embodiment is constituted as a process unit 6 wherein the four process devices, that is, the photosensitive drum 1, the charging blade 2, the developing unit 7 and the cleaning unit 9, are incorporated as a unit with a predetermined mutual positional relationship.
  • the process unit 6 can be mounted by inserting it into the main body of the image forming apparatus along supporting rails 12, 12' in the direction perpendicular to the plane of FIG. 2.
  • the process unit 6 is also detachable from the main body of the image forming apparatus.
  • the process unit 6 may comprise the photosensitive drum 1 and the charging blade 2.
  • the main body of the apparatus and the process unit 6 are mechanically and electrically coupled with each other, and the image forming apparatus assumes an operable state.
  • FIG. 1 is a model diagram of the contact charging device portion of the image forming apparatus shown in FIG. 2.
  • the substrate of the charging blade 2 is, for example, an elastic rubber blade 2a which is 1 - 2 mm thick and which is made of hydrin, EPDM (ethylene/propylene/diene terpolymer), urethane or the like whose volume resistivity is controlled to about 10 7 - 10 9 ⁇ cm.
  • the base portion of the charging blade 2 is mounted on a conductive rigid supporting member 4, made of a steel plate or the like, as a unit using an adhesive or the like.
  • the charging blade 2 and the supporting member 4 are molded and held as a unit by injecting the blade material into a metal mold.
  • the distal end of the charging blade 2 contacts the photosensitive drum 1 in the counter direction (the contact angle is an acute angle) relative to the rotation of the photosensitive drum 1.
  • the contact of the charging blade 2 with the photosensitive drum 1 may also be in the forward direction (the contact angle is an obtuse angle) relative to the rotation of the photosensitive drum 1.
  • the contact charging member includes the charging blade 2 having the rubber blade 2a and the electrode layer 3, and the supporting member 4.
  • a power supply 5 for applying a voltage to the charging blade 2 applies to the conductive rigid supporting member 4 of the charging blade 2, for example, a DC voltage corresponding to a potential necessary for the photosensitive drum 1, or a bias voltage obtained by superposing an alternating voltage having a peak-to-peak voltage at least twice the discharge starting voltage (V TH ) determined from the charging blade 2 and the photosensitive drum 1 with the DC voltage in order to obtain uniform charging.
  • V TH discharge starting voltage
  • the above-described superposed bias voltage is a voltage whose value periodically changes. It may, for example, be a sinusoidal-wave AC voltage, or a rectangular-wave AC voltage which is formed by periodically switching on and off a DC power supply.
  • the rubber blade 2a serving as the substrate of the charging blade 2 is sized to provide two sheets of charging blades having a predetermined size. If the rubber blade 2a is cut along its longitudinal central axis C - C, two charging blade substrates having the predetermined size are obtained.
  • Conductive rigid supporting members 4, 4' are connected to the left and right side portions of the rubber blade 2a having the size for two sheets as one body symmetrically relative to the axis C - C using an adhesive or the like.
  • the back electrode 3 having a volume resistivity of 10 2 - 10 3 ⁇ ⁇ cm and having a cross-like patterned region, as shown by hatching, is formed as a layer symmetrically relative to the longitudinal central axis C - C by printing with a conductive paint made, for example, of polyurethane and the like on the back of the rubber blade 2a. Any material having a volume resistivity of 10 5 ⁇ ⁇ cm or less may be used for the back electrode 3.
  • the supporting members 4, 4' and the back electrode 3 are electrically connected by forming part of the back electrode 3 so as to extend on respective surfaces of the previously connected supporting members 4, 4'.
  • two charging blades 2 are obtained by cutting the rubber blade 2a along the longitudinal central axis C - C.
  • the back electrode 3 As described above, by forming the back electrode 3 as a layer over the supporting members 4, 4' from the back of the rubber blade 2a after connecting the rubber blade 2a to the supporting members 4, 4', the supporting members 4, 4' and the rubber blade 2a can be electrically connected at the same time as the back electrode 3 is provided. Hence, the production process of the charging member is simplified.
  • the charging member is formed by connecting the back electrode 3 and the supporting member 4 so as to superpose with each other after forming the back electrode on the rubber blade 2a, and the photosensitive drum 1 is rotatably moved while contacting the charging blade 2 to the photosensitive drum 1, the connected portion may easily peel according to a state wherein the back electrode 3 is formed, or the positional accuracy of the charging blade 2 or the back electrode 3 relative to the photosensitive drum 1 may decrease.
  • an adhesive is used for connecting the back electrode 3 and the supporting member 4 by superposing them, the adhesive must be conductive. Hence, the usable range of adhesives is limited.
  • the connecting force between the rubber blade 2a and the supporting member 4 can be stabilized for a long period, and the positional accuracy of the charging blade 2a relative to the photosensitive drum 1 increases. As a result, it is possible to perform stable charging. In addition, the usable range of adhesives is increased.
  • the back electrode 3 need not be formed on the entire surface of the back of the rubber blade 2a, but it is sufficient if there are a back portion of the rubber blade 2a corresponding to the distal-end portion of the rubber blade 2a in contact with the member 1 to be charged, and a connecting portion for electrically connecting that portion to the supporting member 4, serving as the voltage supply side, as the T-like pattern (the pattern after cutting along the axis C - C) in the present embodiment.
  • a back electrode 3 1 is formed as a layer by coating an electrode-layer material on the back of the rubber blade 2a after the connection/cutting, as shown in FIG. 3(B), electric charge leaks may occur in some cases, for example, due to the movement of the coated electrode-layer material in the neighborhood of the contact portion, as shown by reference numeral 32 in FIG. 3(C).
  • the width of the rubber blade 2a may be increased by ⁇ and ⁇ at its right and left end sides, respectively, the supporting members 4, 4' may be attached to the rubber blade 2a, and the back electrode 3 may then be formed. Subsequently, the rubber blade 2a may be cut along its central axis C - C, and the extra widths ⁇ and ⁇ at the right and left end sides may be removed by cutting along lines U 1 - U 1 and U 2 - U 2 .
  • an excellent finish accuracy for the right and left end sides of the rubber blade 2a can be obtained, as shown in FIG. 5(B), and it is possible to eliminate the trouble of electric charge leaks due to the movement of the electrode-layer material onto the right and left end sides.
  • the pattern of the back electrode 3 in the embodiment shown in FIGS. 5(A) and 5(B) has a ]-like shape composed of a portion along the distal-end side of the rubber blade 2a and portions along the right and left end sides of the rubber blade 2a on the back of the rubber blade 2a.
  • the back electrode 3 may be coated on the entire surface of the back of the rubber blade 2a.
  • the back electrode 3 may be first formed on the entire surface of the back of the rubber blade 2a using spray coating followed by the above-described cutting process.
  • the rubber blade 2a may be cut along its center line C - C.
  • the charging blade 2 may also be composed of a sheet material or a film material.
  • the back electrode 3 may be formed and configured in the same manner as explained above.
  • the present invention has the following effects: By forming an electrode layer on a charging blade, serving as a contact charging member, after connecting the blade to its supporting member as one body, it is possible to stabilize the connecting force between the two members for a long period, to accurately contact the blade to a member to be charged and thereby perform stable charging, and to simplify the production process of the charging member.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Plasma & Fusion (AREA)
  • General Physics & Mathematics (AREA)
  • Electrostatic Charge, Transfer And Separation In Electrography (AREA)

Claims (23)

  1. Aufladeelement zum Aufladen eines aufzuladenden Bauelementes, das
    - eine Lamelle (2) und
    - ein Stützelement (4) zum Befestigen der Lamelle aufweist,
    gekennzeichnet durch
    eine Elektrodenschicht (3), die nach dem Verbinden der Lamelle mit dem Stützelement auf der Rückseite der mit dem aufzuladenden Bauelement in Berührung stehenden Lamelle erzeugt wird, wobei die Elektrodenschicht sich mindestens partiell auf dem Stützelement erstreckt, um eine elektrische Verbindung zwischen der Lamelle und dem Stützelement herzustellen.
  2. Aufladeelement gemäß Anspruch 1, dadurch gekennzeichnet, daß in Längsrichtung des aufzuladenden Bauelementes gesehen die Breite der Lamelle (2) größer ist als die Breite der Elektrodenschicht (3).
  3. Aufladeelement gemäß Anspruch 1, dadurch gekennzeichnet, daß die Lamelle (2) aus einem elastischen Material hergestellt ist.
  4. Aufladeelement gemäß Anspruch 1, dadurch gekennzeichnet, daß das Stützelement (4) aus einem leitenden Material hergestellt ist.
  5. Aufladeelement gemäß Anspruch 4, dadurch gekennzeichnet, daß das Stützelement (4) starr ist.
  6. Aufladeelement gemäß Anspruch 4, dadurch gekennzeichnet, daß dieses Element eine Vorrichtung zum Anlegen einer Spannung an das Stützelement (4) aufweist, um das Aufladen durchzuführen.
  7. Arbeitseinheit, die von einem elektrofotografischen Bilderzeugungsgerät abgenommen werden kann und die aufweist
    - ein Bauelement mit einem aufgenommenen Bild (1) und
    - eine Aufladevorrichtung (2, 4) zum Aufladen des Bauelementes mit dem aufgenommenen Bild, wobei die Aufladevorrichtung sich aus einer das Bauelement mit dem aufgenommenen Bild berührenden Lamelle (2) und einem Stützelement (4) zum Befestigen der Lamelle zusammensetzt,
    gekennzeichnet durch
    eine Elektrodenschicht (3), die nach dem Verbinden der Lamelle mit dem Stützelement auf der Rückseite der das Bauelement mit dem aufgenommenen Bild berührenden Lamelle erzeugt wird, wobei die Elektrodenschicht sich mindestens partiell auf dem Stützelement erstreckt, um eine elektrische Verbindung zwischen der Lamelle und dem Stützelement herzustellen.
  8. Arbeitseinheit gemäß Anspruch 7, dadurch gekennzeichnet, daß diese außerdem eine Vorrichtung (7) zum Entwickeln des auf dem Bauelement (1) aufgenommenen und aufgeladenen latenten Bildes aufweist.
  9. Arbeitseinheit gemäß Anspruch 7, dadurch gekennzeichnet, daß das Bauelement mit dem aufgenommenen Bild (1) drehbar und die Breite der Lamelle (2) größer ist als die Breite der Elektrodenschicht (3) in Längsrichtung des drehbaren Bauelementes mit dem aufgenommenen Bild (1) gesehen.
  10. Arbeitseinheit gemäß Anspruch 7, dadurch gekennzeichnet, daß die Lamelle (2) aus einem elastischen Material hergestellt ist.
  11. Arbeitseinheit gemäß Anspruch 7, dadurch gekennzeichnet, daß das Stützelement (4) aus einem leitenden Material hergestellt ist.
  12. Arbeitseinheit gemäß Anspruch 7, dadurch gekennzeichnet, daß das Stützelement starr ist.
  13. Arbeitseinheit gemäß Anspruch 7, dadurch gekennzeichnet, daß diese außerdem eine Vorrichtung (5) zum Anlegen einer Spannung an das Stützelement (4) aufweist, um das Aufladen durchzuführen.
  14. Elektrofotografisches Bilderzeugungsgerät, das aufweist
    - ein Bildaufnahmeelement (1),
    - eine Bilderzeugungsvorrichtung (L) zum Erzeugen eines Bildes auf dem Bildaufnahmeelement und
    - eine Aufladevorrichtung (2, 4) zum Aufladen des Bildaufnahmeelementes, wobei die Aufladevorrichtung eine Lamelle (2) zum Berühren des Bildaufnahmeelementes und ein Stützelement (4) zum Befestigen der Lamelle aufweist,
    gekennzeichnet durch
    eine Elektrodenschicht (3), die nach dem Befestigen der Lamelle am Stützelement auf der Rückseite der das Bildaufnahmeelement berührenden Lamelle erzeugt wird, wobei die Elektrodenschicht sich mindestens partiell auf dem Stützelement (4) erstreckt, um eine elektrische Verbindung zwischen der Lamelle und dem Stützelement herzustellen.
  15. Bilderzeugungsgerät gemäß Anspruch 14, dadurch gekennzeichnet, daß das Bildaufnahmelement drehbar und die Breite der Lamelle (2) größer ist als die Breite der Elektrodenschicht (3) in Längsrichtung des drehbaren Bildaufnahmeelementes gesehen.
  16. Bilderzeugungsgerät gemäß Anspruch 14, dadurch gekennzeichnet, daß die Lamelle (2) aus einem elastischen Material hergestellt ist.
  17. Bilderzeugungsgerät gemäß Anspruch 14, dadurch gekennzeichnet, daß das Stützelement (4) aus einem leitenden Material hergestellt ist.
  18. Bilderzeugungsgerät gemäß Anspruch 14, dadurch gekennzeichnet, daß das Stützelement (4) starr ist.
  19. Bilderezeugungsgerät gemäß Anspruch 17, dadurch gekennzeichnet, daß dieses außerdem eine Vorrichtung (5) zum Anlegen einer Spannung an das Stützelement (4) aufweist, um das Aufladen durchzuführen.
  20. Verfahren zur Herstellung eines Aufladeelementes für ein aufzuladendes Bauelement, das die Schritte aufweist
    - Bereitstellung einer Lamelle (2),
    - Bereitstellung eines Stützelementes (4) und
    - Befestigen der Lamelle am Stützelement,
    und das gekennzeichnet ist durch
    die Erzeugung einer Elektrodenschicht (3) auf der Rückseite der das Bildaufnahmeelement berührenden Lamelle nach dem Befestigen der Lamelle am Stützelement, wobei die Elektrodenschicht sich mindestens partiell auf dem Stützelement (4) erstreckt, um eine elektrische Verbindung zwischen der Lamelle und dem Stützelement herzustellen.
  21. Verfahren gemäß Anspruch 20, dadurch gekennzeichnet, daß dieses außerdem den Verfahrensschritt aufweist, bei dem die Lamelle (2) in einer größeren Breite als die Elektrodenschicht (3) in Längsrichtung des vom Aufladeelement aufzuladenden Bauelementes gesehen erzeugt wird.
  22. Verfahren gemäß Anspruch 20, dadurch gekennzeichnet, daß dieses außerdem den Verfahrensschritt der Herstellung der Lamelle (2) aus einem elastischen Material aufweist.
  23. Verfahren gemäß Anspruch 20, dadurch gekennzeichnet, daß dieses außerdem den Verfahrensschritt der Verwendung eines starren Stützelementes (4) aufweist.
EP19910100831 1990-01-24 1991-01-23 Auflade-Element mit einer Elektrodenstruktur und dieses verwendende Aufladevorrichtung in einer abnehmbaren Arbeitseinheit für ein Bilderzeugungsgerät Expired - Lifetime EP0439145B1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP14095/90 1990-01-24
JP2014095A JP2767951B2 (ja) 1990-01-24 1990-01-24 接触帯電部材

Publications (3)

Publication Number Publication Date
EP0439145A2 EP0439145A2 (de) 1991-07-31
EP0439145A3 EP0439145A3 (en) 1992-12-09
EP0439145B1 true EP0439145B1 (de) 1996-09-04

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EP19910100831 Expired - Lifetime EP0439145B1 (de) 1990-01-24 1991-01-23 Auflade-Element mit einer Elektrodenstruktur und dieses verwendende Aufladevorrichtung in einer abnehmbaren Arbeitseinheit für ein Bilderzeugungsgerät

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EP (1) EP0439145B1 (de)
JP (1) JP2767951B2 (de)
DE (1) DE69121731T2 (de)

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0439143A3 (en) * 1990-01-24 1992-12-09 Canon Kabushiki Kaisha Charging member featureing a cut edge, and charging device employing same for use in a detachable process unit in an image forming apparatus
JP3028617B2 (ja) * 1991-02-06 2000-04-04 ミノルタ株式会社 接触帯電装置
JP3339877B2 (ja) * 1992-05-15 2002-10-28 ミノルタ株式会社 接触帯電装置
JP5677068B2 (ja) * 2010-12-14 2015-02-25 キヤノン株式会社 帯電部材および画像形成装置

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0308185B1 (de) * 1987-09-14 1993-11-24 Canon Kabushiki Kaisha Aufladevorrichtung
DE3889708T2 (de) * 1987-10-05 1994-09-22 Canon Kk Bilderzeugungsgerät.
EP0439143A3 (en) * 1990-01-24 1992-12-09 Canon Kabushiki Kaisha Charging member featureing a cut edge, and charging device employing same for use in a detachable process unit in an image forming apparatus

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Publication number Publication date
EP0439145A3 (en) 1992-12-09
JPH03217874A (ja) 1991-09-25
JP2767951B2 (ja) 1998-06-25
DE69121731D1 (de) 1996-10-10
EP0439145A2 (de) 1991-07-31
DE69121731T2 (de) 1997-02-06

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