Samsung Electronics Co., Ltd.

Ki-jae Do

Sang-jin Park

In-cheol Jeon

Jong-hwa Joo

Hee-Won Jung

Yong-hoon Lee

Ji-won Moon

Jong-woo Park

Jun-Ho Kim

Woong-Yong Choi

Tae-hyun Kim

Won Choe

Hyun-wook Bae

Jeong-seon Kim

In-Cheol Jeon

Byoung-chul Bae

Jong-uk Kim

Valery KrasnosloBoditsev

Hee-won Jung

A developing roller including a housing containing toner; and a developing roller installed in the housing and supplies the toner to an electrostatic latent image formed on a photoconductor, the developing roller including a cylindrical unit in the form of a hollow pipe and a power transmission unit connected to one end of the cylindrical unit and connected to a power transmission member for rotating the developing roller. Both ends of the cylindrical unit are supported by the housing and the power transmission unit is not restricted by the housing. Both ends of the cylindrical unit are supported by the housing and the power transmission unit is not restricted by the housing.

Developing device and image forming apparatus including the same

An image forming apparatus includes a plurality of developing devices to develop toners of different colors on an image carrier; a power supply to supply the plurality of developing devices with a first voltage to develop the toners on the image carrier; a switching unit to connect the power supply to one of the plurality of developing devices; and a voltage divider to supply some of the other developing devices that are not connected to the power supply with a second voltage to prevent toner development and to supply any other remaining developing device with a third voltage, an absolute value of which is less then an absolute value of the second voltage.

Multi-pass image forming apparatus having voltage divider

A charging apparatus including a charging tube which has an outer surface contacting a photoconductive medium and electrically charges a surface of the photoconductive medium, a shaft which is disposed in the charging tube and to which a charging voltage is applied, and a conductive member which is connected to the shaft and contacts an inner surface of the charging tube. A friction coefficient between the conductive member and the inner surface of the charging tube may be less than a friction coefficient between the photoconductive medium and the outer surface of the charging tube, so that a slip phenomenon of the charging tube is prevented.

Charging apparatus using charging tube and image forming apparatus having the same

A roller for use in a developing unit of an image forming apparatus may include a non-conductive shaft member and a non-conductive member to surround at least a part of an outer periphery of the shaft member. The shaft member may include a cylindrical rolling part and a pair of support parts formed to project from both ends of the rolling part in a lengthwise direction. The rolling part of the shaft member may be arranged opposite a charge roller in a developing unit and may rotate in contact with the charge roller to absorb and remove foreign substances adhered to a surface of the charge roller.

Roller, developing unit and image forming apparatus having the same, and method of manufacturing roller

An electrophotographic image forming apparatus including first and second photosensitive bodies, first and second exposing units to form electrostatic latent images on the first and second photosensitive bodies respectively charged to a uniform electric potential, a first developing unit to develop an electrostatic latent image of the first photosensitive body by supplying a color toner to the electrostatic latent image of the first photosensitive body, and a second developing unit in which a transparent toner and a white toner charged to different polarities are contained and which develops a transparent toner image and a white toner image by respectively supplying the transparent toner and the white toner to an image portion and a non-image portion of an electrostatic latent image of the second photosensitive body.

Electrophotographic image forming apparatus having transparent toner and white toner

An electro photographic image forming apparatus includes first and second photosensitive bodies, first and second exposing units to form electrostatic latent images on the first and second photosensitive bodies each of which being charged to a uniform electric potential, a first developing unit to develop the electrostatic latent image on the first photosensitive body by supplying a transparent toner thereto, and a second developing unit to develop the electrostatic latent image on the second photosensitive body by supplying color toners thereto, wherein the first developing unit is a developing unit employing a two-component developing technique using a magnetic carrier and a transparent toner.

Electrophotographic image forming apparatus having transparent toner

A developing unit of an image forming apparatus includes a developing member to develop an electrostatic latent image on a photosensitive medium with a developer, a first feed member to feed the developer to the developing member, and a reset member disposed above the developing member to reset the developing member. Accordingly, expenditure for consumables is reduced, because a developer cartridge is separately provided. Additionally, efficient developer agitation is provided. Furthermore, a consistent image quality is achieved, because a plurality of augers move vertically and horizontally to circulate the developer inside the developing unit.

Developer cartridge guide unit and image forming apparatus having the same

An image forming apparatus and method for controlling a charge of a toner are provided. The apparatus and method includes a toner supplying roller; a developing roller for supplying the toner to an organic photoconductor; a charge controller for adjusting the charge of the toner on the developing roller; a developing current detector for detecting a change in current for a developing voltage; and a charge controlling voltage controller for adjusting a charge controlling voltage according to the detection result. The apparatus can uniformly maintain the quality of an image by recognizing a change in the charge of toner based on a change in the environment. Also, the image forming apparatus indicates a proper toner replacement time by determining when the charge of the toner is abnormally low as a toner shortage state and displaying the toner shortage state on a panel operating unit.

Image forming apparatus controlling charge of toner and method thereof

An electro-photographic image forming apparatus preventing toner from scattering during a printing operation and a control method of the same. The electro-photographic image forming apparatus includes a scattering preventive member being disposed downstream of the developing roller at a predetermined distance from the photosensitive medium, and a voltage being applied, and a controller controlling the voltage that is applied to the scattering preventive member so as to transport the toner attached on the scattering preventive member to the photosensitive medium.

Electro-photographic image forming apparatus having a function for preventing toner for scattering and control method for the same

A developing device having a developing gap detecting function includes a photosensitive medium, a developer conveyer, a DC power source, an AC power source, a current detecting unit and a controller. The current detecting unit detects a DC current flowing on the developer conveyer when toner from the developer conveyer is attached to a desired area of an electrostatic latent image on a photosensitive body by enhancing a voltage outputted from a power supply gradually at proper intervals. The controller obtains a developing gap between the photosensitive medium and the developer conveyer based on current values detected by the current detecting unit. In accordance with the developing device having the developing gap detecting function, the developing gap is sensed and developing voltage is easily and correctly calculated to control image forming conditions. As a result, an image quality improves.

Developing device having developing gap detecting function

A toner layer regulating member and a developing device using the toner layer regulating member. The toner layer regulating member forms a uniform toner layer on a toner transfer unit, electrically charges a toner by friction, and includes a polyolefin-based elastic rubber member which contacts the outer circumference surface of the toner transfer unit and whose surface is ultraviolet-treated. Thus, a uniform toner layer can be formed on the toner transfer unit and the toner is electrically charged by friction. As a result, a high quality image having no defects can be provided.

Growing community of inventors

Suwon-si, South Korea

Ki-jae Do