Minolta Company, Ltd.

Minolta Camera Kabushiki Kaisha

Kabushiki Kaisha Inoac Corporation

Kouji Matsushita

Yasuhiro Nakagami

Noboru Yonekawa

Shizuo Yuge

Futoshi Okazaki

Hidetoshi Kawabata

Yasunori Nakayama

Munenori Nakano

Tsugihito Yoshiyama

Katsuhiko Takeda

Sanji Inagaki

Kazuyoshi Hara

Kuniaki Kashiwakura

Noboru Ito

Masataka Oda

Keigo Tange

Nobuaki Nishioka

Hisashi Myochin

Hidekazu Nakagami

Yoshihiro Shojo

Shingo Hirota

Mineo Yamamoto

Tatsumi Makio

Tomohiko Teranishi

Ikuro Chimoto

Koichiro Higashiguchi

Takeshi Suzuki

Tetsuya Okashita

In an imaging cartridge for forming images at least including a corona charging device and an object to be charged, a discharging electrode unit in the corona charging device is supported in such a manner that the electrode unit can be separately detached therefrom and installed thereto without being obstructed by the object to be charged or by a grid electrode from a side opposite to the member to be charged.

Imaging cartridge for use in an image forming apparatus including detachable electrode member

A corona discharge device used in an electrophotographic image forming apparatus includes a discharge member such as a saw-toothed discharge member having sharp discharge ends, and a power supply which applies to the discharge member a discharge voltage containing at least an AC voltage component, wherein at least each discharge end portion of the discharge member is made of an electrically conductive material, which contains nickel and chromium, and/or is coated with a material having a high electric resistance. In the case where the saw-toothed discharge member is employed, a distance D between the discharge end and a member to be charged, and a discharge end pitch P are determined to satisfy a relationship of 2&lE;D/P&lE;8.

Corona discharge device

A liquid spreading device for spreading liquid over a target surface to be moved relatively to the liquid spreading device in a predetermined direction, including: a regulating member which is brought into contact with the target surface through the liquid; and a voltage applying unit for applying an electrical bias voltage across the regulating member and the target surface. A fixing device for fixing a toner image onto an image bearing surface of a recording sheet, including: a rotating member having an outer surface to be in contact with the image bearing surface; a regulating member which is brought into contact with the outer surface of the rotating member through the liquid; and a voltage applying unit for applying an electrical bias voltage across the regulating member and the outer surface of the rotating member. A fixing device including: a rotating member having an outer surface to be in contact with the image bearing surface; a spreading roller which is provided for spreading liquid over the outer surface of the rotating member and has an outer surface in contact with the outer surface of the rotating member; a regulating member which is brought into contact with the outer surface of the spreading roller through the liquid; and a voltage applying unit for applying an electrical bias voltage across the regulating member and the outer surface of the spreading roller.

Liquid spreading device and a fixing device

The purpose of the present invention is to provide a conductive contact material, the contents of which do not generate soil on a charged body not only during initial use but also after repeated use. A conductive contact material consists of thermoset urethane material containing an antioxidant within a range from 0.1 to 0.3% by weight, and an inorganic ion electrically conducting agent with in a range form 0.01 to 2.00% by weight. After ozone exposure or the like, molecule chain scission of the base material and antioxidant leads generation of active monomers and origomers. However, the conductive contact material containing the above specified proportion of an antioxidant and an inorganic ion electrically conducting agent prevents generation of active monomers and origomers which are soiling source for a charged body. The conductive contact material also prevents antioxidant itself from being a soiling source. The employment of conductive contact material on a contact type charging device such as a transfer roller avoids disadvantages such as image noise caused by soil on a charged body without involving a large image forming apparatus and complex manufacturing process.

Conductive contact material

Image density is detected by a B/W ratio detection integrator 30 via a video signal 11 from a video controller 40 when an image signal is inputted. When a latent image formed on a photosensitive body 7 in accordance with the image signal is transferred to a transfer material 12 by a transfer charging device 8, a transfer current of the transfer charging device 8 is controlled in a timely fashion by a CPU 20 in accordance with the image density detected from this image signal, thus ensuring optimum transfer efficiency. Even when the environment and printing pattern change for each part of a single-page image, this makes it possible to deal accurately with these changes to ensure stable transfer efficiency and good imaging.

Image formation device

A charging member is disposed so as to contact a surface of a charge-receiving member which moves relative to the charging member. In conjunction with the movement of the charge receiving member, the charging member removes foreign substance present on the charge-receiving member on the upstream side in the direction of travel of the charge-receiving member at the contact region with the charging member. Simultaneously, a discharge voltage is applied to the charging member so that the charging member charges the charge-receiving member in the area from which said foreign substance has been removed at the contact region on the downstream side of the charge-receiving member in the direction of travel of the charge-receiving member. During a cleaning operation, the charging member retracts from the charge-receiving member and is out of contact therewith in accordance with the number of image formations, black and white ratio, and humidity. The removed foreign substance passes by said charging member in conjunction with the movement of the charge-receiving member.

Image forming apparatus provided with contact-type charger and

A charging device K is provided with a flexible electrode 12 and a flexible intermediate member M disposed between the flexible electrode 12 and a charge-receiving member 10, with the flexible intermediate member M being in contact with the charge-receiving member 10. The flexible intermediate member M includes a flexible insulated member 11 and semiconductive member 14 so as to charge the charge-receiving member 10 via a discharge from electrode 12. The absolute value of the difference between the potential of the flexible electrode 12 during discharge and the potential in the vicinity of at least the area of discharge of the flexible electrode 12 among areas in which the flexible intermediate member is in contact with the charge-receiving member 10, is less than the absolute value of the difference between the potential of the charge-receiving member and the potential of the flexible electrode during discharge.

Charging device for image forming apparatus

This invention relates to the charging member portion of an image forming apparatus. A plurality of charging members are disclosed that maintain a uniform spacing between a charge-receiving member and the discharging portion of the charging members' electrodes despite surface irregularities and surface waviness on the charge-receiving member. One charging member is in the form of a flexible sheet provided with ventilation holes in a non-contacting portion thereof, permitting the air produced by the rotation of the charge-receiving member to escape through the holes to suppress the lifting of the charging member. Pressure fins can be added to the charging member on the downstream of the ventilation holes for further suppressing any lifting. Another charging member includes a semiconductive member or a electret member on at least the surface of the charging member on the side opposite the charge-receiving member. This permits the charging member to be electrostatically attracted to the charge-receiving member.

An image forming apparatus and a cleaning blade employed in the image forming apparatus which is operable to form an electrostatic latent image on an image carrying member, develop the latent image with toner into a visible toner image, transfer the toner image onto a record member and fix the same, and having an edge pressed against the image carrying member with a predetermined pressure for removing residual toner on the image carrying member after the transfer. A degree of toluene swelling of the cleaning blade is in a range from 20% to 100%, and the cleaning blade has an impact resilience in a range from 10% to 65%, a Young's modulus in a range from 30 to 120 kg/cm.sup.2, and a 300%-modulus in a range from 100 to 600 kg/cm.sup.2.

Image forming apparatus and cleaning blade

An image forming apparatus having an electrostatic latent image carrier, and a charging device which includes an electric discharge electrode having a plurality of projection and a grid electrode located between the electric discharge electrode and the surface of the electrostatic latent image carrier. A grid electrode electric current Ig passing through the grid electrode and an image carrier electric current Ip passing through the conductive base of electrostatic latent image carrier satisfy the following relationship:

Image forming apparatus with charging device having projecting zip

An image forming apparatus, including a laminate image-bearing member having a dielectric layer or photoconductive layer, superimposed on an electrically conductive substrate, a transfer member for making pressure contact with said image-bearing member, and a cleaning member for cleaning the surface of said image-bearing member through contact therewith, forms an electrostatic latent image on said image-bearing member, develops said latent image into a visible toner image, and transfers said toner image from said image-bearing member to a transfer sheet passing through a contact-pressure nip portion between said image-bearing member and a transfer member by applying a controlled constant-current regulated transfer bias voltage to said transfer member. Where the transfer member is narrower than the dielectric layer, or photoconductive layer, of the image-bearing member and the width of the cleaning member so as to be arranged within said widths, a controller changes the transfer current of constant-current regulated transfer bias in accordance with the thickness of the dielectric layer or photoconductive layer of the image-bearing member.

Image forming apparatus having transfer constant current source

A charging device with a plate-like electrode having a plurality of protrusions, the charging device having a cleaning device including cleaning members which are positioned bilaterally to the electrode and grip the electrode therebetween to clean. The cleaning device cleans the electrode while the cleaning members slide on a guide formed along the electrode, or the cleaning device cleans the electrode by griping the electrode by the cleaning members which are positioned along the electrode.

Charging device having a plate electrode and a cleaning device for

Grid wires arranged in an axial direction of a photoconductive drum have a positional relation with projecting electrodes arranged at regular intervals in an axial direction of the photoconductive drum at a position opposite to the surface of the photoconductive drum wherein the grid wires and the projecting electrodes positioned adjacent to each other are equally arranged in distance to uniformly discharge an electric charge to the surface of the photoconductive drum from each of the projecting electrodes so that uniform charging can be accomplished in an axial direction of the photoconductive drum.

An electrostatic latent image developing apparatus has a developing sleeve drivingly rotatable for supplying a magnetic developer to an image bearing surface of an electrostatic latent image bearing member, a casing covering at least a portion of the developing sleeve and extending from a portion where the sleeve is opposed to the electrostatic latent image bearing member to a position where the developer is supplied to the sleeve with respect to the direction of rotation of the developing sleeve, the casing defining a gap with the sleeve, magnets fixedly positioned in the sleeve and having a plurality of poles opposed to the casing, the plurality of poles including first and second poles of same polarity and a third pole of different polarity, the first and second poles being positioned adjacently with no pole therebetween, whereby a first bristle of developer for sealing the gap is formed by the first and second poles and a second bristle of developer for sealing the gap is formed by the third pole.

Electrostatic latent image developing apparatus

A copying machine of the present invention measures light transmittance of a document so as to adjust copying concentration on the basis of the measured result. The copying concentration is concretely adjusted by adjusting electrification voltage of a photosensitive body, and/or developing bias voltage, and/or quantity of exposure light. The copying machine is free from the occurrence of back image copying when a document is double-faced. A copying machine of the present invention further comprises means for discriminating whether the document is a double-faced one or a single-faced one.

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Toyokawa, Japan

Kouji Matsushita