Canon Kabushiki Kaisha

Kazunori Hashimoto

Masahiro Yoshida

Hisashi Yamauchi

Masahiro Shibata

Kazuhiro Okubo

Seiji Yamaguchi

Masanobu Saito

Yasunari Watanabe

Masato Koyanagi

Tetsuya Kobayashi

Masamichi Sato

Shinji Katagiri

Hiroomi Matsuzaki

Makoto Hayashida

Toshiaki Takeuchi

Yoshihiro Mitsui

Yuhei Terui

Yoshiro Saito

Fumito Nonaka

Kohei Matsuda

Kazuki Matsumoto

Tomonori Matsunaga

Yuichiro Hirata

Takayuki Kanazawa

Yasushi Katsuta

Noriyoshi Umeda

Bunro Noguchi

Go Shindo

Tsuyoshi Nakagawa

Norihisa Hoshika

Shohei Kototani

Yasukazu Ikami

Kosuke Ikada

Yasunori Toriyama

Keitaro Nakata

Tetsuya Nishiguchi

Katsuhiro Kojima

Gosuke Goto

Junko Hirata

Akinobu Saito

An image forming apparatus, to which a cartridge including a developer accommodating portion for accommodating a developer is detachably mountable, includes an image bearing member, an exposure unit configured to expose the image bearing member to light to form an electrostatic latent image on the image bearing member, a light receiving sensor provided in the cartridge and configured to receive the light emitted from the exposure unit, and a controller configured to detect vibration of the cartridge from a light reception value of the light received by the light receiving sensor. In a case in which the cartridge is removed from the image forming apparatus, the light receiving sensor is removed from the image forming apparatus together with the cartridge.

Image forming apparatus

An image forming apparatus includes first and second image forming portions and a belt. The first and second image forming portions include first and second image bearing members, and first and second transferring members, respectively. The belt nips and feeds a recording material. The first image forming portion is disposed upstream of the second image forming portion in a moving direction of the recording material, and a plurality of members including the first and second image bearing members are integrally assembled and are mountable on or dismountable from a main assembly of the image forming apparatus. A film thickness of a surface of the first image bearing member is larger than a film thickness of a surface of the second image bearing member, circumferential speed ratios or contact pressures of rotating components differ, and/or mass ratios of components of respective developers differ.

Image forming apparatus for prolonging life of replaceable image forming unit

A process cartridge includes a seal member contacting an image bearing member upstream in the rotation direction of the image bearing member from a cleaning member and allowing the developer to move from upstream in the rotation direction from the contact part between the seal member and the image bearing to downstream from the contact part while regulating movement from downstream to upstream from the contact part. The developer has surface protrusions containing an organic silicon polymer, wherein either (i) the work function of the seal member is greater than the work function of the developer when the developer has a negative charging polarity and is smaller than the work function of the developer when the developer has a positive charging polarity, or (ii) the absolute value of the difference between the work function of the seal member and the work function of the developer is within a predetermined range.

Process cartridge, image forming apparatus and cleaning apparatus

A developing device includes a developer bearing member that bears a developer on its surface to supply the developer to an image bearing member having a first dielectric portion and a second dielectric portion in its surface, a regulating member that regulates a thickness of a layer of the developer carried by the developer bearing member, and a flexible sheet-like charging auxiliary member disposed so as to be in contact with the developer bearing member at a position downstream of a contact portion between the developer bearing member and the image bearing member and upstream of a contact portion between the developer bearing member and the regulating member in a rotational direction of the developer bearing member, where the charging auxiliary member charges the developer carried by the developer bearing member. In a triboelectric series, the charging auxiliary member is positioned between the first and second dielectric portions.

Developing device and image forming apparatus

An image forming apparatus includes first and second developer carrying members and a control device. The apparatus is operable in a first mode where an image of a single color is formed using the first developer carrying member and is operable in a second mode, wherein an image of a plurality of colors is formed using the first and second developer carrying members. The control device controls a first discharging operation for discharging developer from the first developer carrying member and a second discharging operation for discharging developer from each of the first and second developer carrying members. When the apparatus executes only the first mode, the control device performs more image formations, in a period between completion of the second discharging operation and start of the first discharging operation, compared to a period between completion of the first discharging operation and start of a subsequent first discharging operation.

Image forming apparatus featuring a control device for controlling a developer discharge operation in first and second modes

An image forming apparatus includes a toner carrying member for supplying toner to an image bearing member to visualize the latent image; a rotatable toner supply member, contacted to the toner carrying member, for supplying toner to the image bearing member; a voltage applying device for applying voltages to the toner carrying member and the toner supply member; and a controller for controlling the voltage applying device to control voltages applied to the toner carrying member and the toner supplying member.

A toner supplying roller which is used in a developing apparatus and has the following characteristics: (1) an average diameter of a foam cell opening portion on a surface of a foam elastic member is 100 to 800 &#x3bc;m, (2) an unopened cell closed by a skin layer of a film thickness of 50 &#x3bc;m or less is present in the surface of the foam elastic member, and (3) assuming that a surface area of the foam elastic member is A, a total area of the foam cell opening portions is B, and a surface area of the unopened cell is C, the following relationship is satisfied: 

Toner supplying roller, developing apparatus, and image forming apparatus

The invention realizes a uniform toner coating on a developing roller, thereby preventing a density unevenness and a toner dripping and suppressing a developing roller set mark image in a contact developing method, by conditions that the DC voltage applied to the developer regulating member is the same as the DC voltage applied to the developer carrying member or at a side of a charging polarity of the developer with respect to the DC voltage applied to the developer carrying member; and a frequency f (Hz) and a peak electric field strength E (V/m) of the AC electric field formed by the AC voltage between the developer regulating member and the developer carrying member, and a peripheral speed v (m/s) of the image bearing member satisfy conditions:4.2&#x2266;2500 and2.2&#xd7;10&#x2266;5.2&#xd7;10.

Image forming apparatus with a developer regulating member

A developing apparatus including a developer carrying member for carrying a developer for developing an electrostatic image, formed on an image bearing member, with the developer, a developer regulating member for regulating the developer carried on the developer carrying member, and an oscillating electric field forming device which forms an oscillating electric field between the developer carrying member and the developer regulating member, wherein a developer consuming operation is executed for consuming the developer from the developer carrying member to an image non-forming area of the image bearing member and a period of forming the oscillating electric field is provided in the operation.

Developing apparatus

An image forming apparatus includes a plurality of developing devices each including a developer carrying member for carrying a developer to develop an electrostatic latent image formed on an image bearing member, and a developer regulating member for regulating the developer carried on the developer carrying member; a common voltage applying device for applying a common voltage to the plurality of the developer regulating member. When a first one of the developer carrying members is rotating, and when a second one of the developer carrying members is not rotating, a potential difference between a potential of the second developer carrying member and the common voltage is smaller than a potential difference between a potential of the first developer carrying member and the common voltage.

Image forming apparatus including two developer carrying members wherein potential differences between the developer carrying members and a common voltage source differ

An image forming apparatus includes a plurality of developing devices, each of which includes a developer carrying member for carrying a developer to develop an electrostatic image formed on an image bearing member with a developer, and a developer regulating member for regulating the developer carried on the developer carrying member; a common voltage applying device for applying voltages to the developer regulating members, wherein the voltages are applied to the developer carrying members are variable independently from each other, and when at least one of the voltages varies, the voltage applied by the voltage applying device is capable of being changed.

Image forming apparatus, wherein voltages applied to developer regulating members are based on respective voltages applied to developer carrying members

A unit detachably attachable to a main body of an image forming apparatus includes developing means for developing a latent image born on an image bearing body and storage means for storing a time which has elapsed from a last developing operation of the developing means.

Developer unit detachably attachable to image forming apparatus

Growing community of inventors

Numazu, Japan

Kazunori Hashimoto